Adrenaline Health Dictionary

Also known as suprarenal glands, these are two small triangular ENDOCRINE GLANDS situated one upon the upper end of each kidney. (See diagram of ABDOMEN.)

Structure Each suprarenal gland has an enveloping layer of ?brous tissue. Within this, the gland shows two distinct parts: an outer, ?rm, deep-yellow cortical (see CORTEX) layer, and a central, soft, dark-brown medullary (see MEDULLA) portion. The cortical part consists of columns of cells running from the surface inwards, whilst in the medullary portion the cells are arranged irregularly and separated from one another by large capillary blood vessels.

Functions Removal of the suprarenal glands in animals is speedily followed by great muscular prostration and death within a few days. In human beings, disease of the suprarenal glands usually causes ADDISON’S DISEASE, in which the chief symptoms are increasing weakness and bronzing of the skin. The medulla of the glands produces a substance – ADRENALINE – the effects of which closely resemble those brought about by activity of the SYMPATHETIC NERVOUS SYSTEM: dilated pupils, hair standing on end, quickening and strengthening of the heartbeat, immobilisation of the gut, increased output of sugar from the liver into the bloodstream. Several hormones (called CORTICOSTEROIDS) are produced in the cortex of the gland and play a vital role in the metabolism of the body. Some (such as aldosterone) control the electrolyte balance of the body and help to maintain the blood pressure and blood volume. Others are concerned in carbohydrate metabolism, whilst others again are concerned with sex physiology. HYDROCORTISONE is the most important hormone of the adrenal cortex, controlling as it does the body’s use of carbohydrates, fats and proteins. It also helps to suppress in?ammatory reactions and has an in?uence on the immune system.... adrenal glands

A precursor of ADRENALINE in the medulla of the suprarenal glands (see ADRENAL GLANDS). It is also present in the BRAIN. Its main function is to mediate the transmission of impulses in the SYMPATHETIC NERVOUS SYSTEM; it also has a transmitter function in the brain.... noradrenaline

A disorder in which a vascular tumour of the adrenal medulla (see ADRENAL GLANDS) develops. The tumour may also affect the structurally similar tissues associated with the chain of sympathetic nerves. There is uncontrolled and irregular secretion of ADRENALINE and NORADRENALINE with the result that the patient suffers from episodes of high blood pressure (HYPERTENSION), raised heart rate, and headache. Surgery to remove the tumour may be possible; if not, drug treatment may help.... phaeochromocytoma

An immediate (and potentially health- or life-threatening) hypersensitivity reaction produced by the body’s immunoglobulin E (IgE) antibodies to a foreign substance (antigen); the affected tissues release histamine which causes local or systemic attack. An example is the pain, swelling, eruption, fever and sometimes collapse that may occur after a wasp sting or ingestion of peanut in a particularly sensitive person. Some people may suffer from anaphylaxis as a result of allergy to other foods or substances such as animal hair or plant leaves. On rare occasions a person may be so sensitive that anaphylaxis may lead to profound SHOCK and collapse which, unless the affected person receives urgent medical attention, including injection of ADRENALINE, may cause death. (See also ALLERGY; IMMUNITY.)... anaphylaxis

Substances produced in the body from the dietary AMINO ACIDS, PHENYLALANINE and TYROSINE. They include ADRENALINE, NORADRENALINE and DOPAMINE which have varying functions, usually as NEUROTRANSMITTERS, in the sympathetic and central nervous systems (see under NERVOUS SYSTEM). Their chemical structure is based on a benzene ring with hydroxyl and amine side-chains.... catecholamines

One of the small ovoid collections of cells occurring in the walls of the ganglia of the SYMPATHETIC NERVOUS SYSTEM adjacent to the SPINAL CORD. They are CHROMAFFIN cells and sometimes secrete ADRENALINE.... paraganglion

A variety of the chemical compound amine, which is derived from ammonia. A sympathomimetic agent with an action which resembles that of ADRENALINE, tyramine occurs in mistletoe, mature cheese, beers, red wine and decaying animal matter. This adrenaline e?ect is potentially dangerous for patients taking MONOAMINE OXIDASE INHIBITORS (MAOIS) – ANTIDEPRESSANT DRUGS – because, when combined with tyramine, the blood pressure rises sharply. Such patients should avoid taking cheese, beers and red wine.... tyramine

An alternative name for adrenaline.... epinephrine

Any factor or event that threatens a person’s health or adversely affects his or her normal functioning. Injury, disease or worry are common examples; others include internal con?icts, emotive life events – such as the death of a close relative or friend, the birth of a baby, separation or divorce – pressures at work or a hostile environment such as war or famine. Some individuals seem to be more prone than others to develop medical problems related to stress.

Stress prompts the body to raise its output of HORMONES such as ADRENALINE and CORTISOL, causing changes in blood pressure, heart rate and metabolism. These are physiological responses intended to improve a person’s physical and mental performance – the ‘?ght or ?ight’ reaction to fear. Stress may, however, disrupt the ability to cope. Constant or recurrent exposure to stress may produce symptoms such as anxiety, depression, headaches, indigestion, diarrhoea, palpitations and general malaise (see POST-TRAUMATIC STRESS DISORDER (PTSD)). Treatment can be di?cult and prolonged; counselling can help as can ANXIOLYTICS or ANTIDEPRESSANT DRUGS – but a change in job or lifestyle may be necessary in some circumstances.... stress

The sites in the body on which ADRENALINE and comparable stimulants of the SYMPATHETIC NERVOUS SYSTEM act. Drugs which have an adrenaline-like action are described as being adrenergic. There are ?ve di?erent types of adrenergic receptors, known as alpha1, alpha2, beta1, beta2 and beta3 respectively. Stimulation of alpha receptors leads to constriction of the bronchi, constriction of the blood vessels with consequent rise in blood pressure, and dilatation of the pupils of the eyes. Stimulation of beta1 receptors quickens the rate and output of the heart, while stimulation of beta2 receptors dilates the bronchi. Beta3 receptors are now known to mediate so-called non-shivering thermogenesis, a way of producing heat from specialised fat cells that is particularly relevant to the human infant.

For long it had been realised that in certain cases of ASTHMA, adrenaline had not the usual bene?cial e?ect of dilating the bronchi during an attack; rather it made the asthma worse. This was due to its acting on both the alpha and beta adrenergic receptors. A derivative, isoprenaline, was therefore produced which acted only on the beta receptors. This had an excellent e?ect in dilating the bronchi, but unfortunately also affected the heart, speeding it up and increasing its output – an undesirable e?ect which meant that isoprenaline had to be used with great care. In due course drugs were produced, such as salbutamol, which act predominantly on the beta2 adrenergic receptors in the bronchi and have relatively little e?ect on the heart.

The converse of this story was the search for what became known as BETA-ADRENOCEPTORBLOCKING DRUGS, or beta-adrenergic-blocking drugs. The theoretical argument was that if such drugs could be synthesised, they could be of value in taking the strain o? the heart – for example: stress ? stimulation of the output of adrenaline ? stimulation of the heart ? increased work for the heart. A drug that could prevent this train of events would be of value, for example in the treatment of ANGINA PECTORIS. Now there is a series of beta-adrenoceptor-blocking drugs of use not only in angina pectoris, but also in various other heart conditions such as disorders of rhythm, as well as high blood pressure. They are also proving valuable in the treatment of anxiety states by preventing disturbing features such as palpitations. Some are useful in the treatment of migraine.... adrenergic receptors

Substances found commonly in various plants. They are natural nitrogenous organic bases and combine with acids to form crystalline salts. Among alkaloids, morphine was discovered in 1805, strychnine in 1818, quinine and ca?eine in 1820, nicotine in 1829, and atropine in 1833. Only a few alkaloids occur in the animal kingdom, the outstanding example being ADRENALINE, which is formed in the medulla of the suprarenal, or adrenal, gland. Alkaloids are often used for medicinal purposes. The name of an alkaloid ends in ‘ine’ (in Latin, ‘ina’).

Neutral principals are crystalline substances with actions similar to those of alkaloids but having a neutral reaction. The name of a neutral principal ends in ‘in’, e.g. digitalin, aloin.

The following are the more important alkaloids, with their source plants:

Aconite, from Monkshood.

Atropine, from Belladonna (juice of Deadly

Nightshade).

Cocaine, from Coca leaves.

Hyoscine, from Henbane.

Morphine, Codeine, from Opium (juice of

Poppy). Thebaine, Nicotine, from Tobacco. Physostigmine, from Calabar beans. Pilocarpine, from Jaborandi leaves. Quinidine, from Cinchona or Peruvian bark. Strychnine, from Nux Vomica seeds.... alkaloids

Also called adrenoceptor-blocking agents or alpha blockers, these drugs stop the stimulation of alpha-adrenergic receptors at the nerve endings of the SYMPATHETIC NERVOUS SYSTEM by HORMONES with ADRENALINE-like characteristics. The drugs dilate the arteries, causing a fall in blood pressure, so they are used to treat HYPERTENSION and also benign enlargement of the PROSTATE GLAND. Examples of this group of drugs are doxazosin, indoramin, phentolamine and prazosin. The drugs should be used with caution as some may cause a severe drop in blood pressure when ?rst taken.... alpha adrenergic blockers

Substances derived from ammonia or AMINO ACIDS which play an important part in the working of the body, including the brain and the circulatory system. They include ADRENALINE, NORADRENALINE and HISTAMINE. (See also MONOAMINE OXIDASE INHIBITORS (MAOIS).)... amines

A group of drugs closely related to ADRENALINE which act by stimulating the SYMPATHETIC NERVOUS SYSTEM. When taken by mouth they have a profound stimulating e?ect on the brain, producing a sense of well-being and con?dence and seemingly increasing the capacity for mental work. They are, however, drugs of DEPENDENCE and their medical use is now strictly limited – for example, to the treatment of NARCOLEPSY.

Because amphetamines inhibit appetite, they rapidly achieved a reputation for slimming purposes. However, they should not be used for this purpose; their dangers far outweigh their advantages.... amphetamines

Linn.

Family: Palmae; Arecaceae.

Habitat: Native to Malaysia; now grown along the coasts of Karnataka, Kerala, Tamil Nadu, West Bengal, Assam and Maharashtra.

English: Arecanut, Betel Nut.

Ayurvedic: Puuga, Puugi, Kramuka, Ghontaa, Guwaak, Ghorant.

Unani: Fufal, Chhaalia, Supaari.

Siddha/Tamil: Kottai Paakku, Kamugu.

Action: Taeniacide (confined to veterinary medicine), astringent, stimulant.

Along with other therapeutic application, The Ayurvedic Pharmacopoeia of India indicates the use of dried ripe seed in leucorrhoea and vaginal laxity.

Arecanut contains several alkaloids belonging to pyridine group, the most important being arecoline (0.1-0.5%). Arecaidine, guvacine and isoguvacine are also present. Arecoline is an- thelmintic (in animals, not in humans). Arecaidine has no parasympa- thomimetic effects, but only stimulating properties; sedative in higher doses. Isoguvacine produces hypotension.

Contraindicated in asthma due to bronchoconstrictive effects of the alkaloid arecoline (human case reports). (Francis Brinker.)

Arecanut tannins (8.0-18.0%) are predominantly catechol tannins which closely resemble Mimosa bark tannins. Powdered nuts are prescribed in diarrhoea and urinary disorders. In combination with other astringent and styptic herbs, arecanut is used as a major constituent in confections of Indian medicine for gynaecological disorders.

Aqueous extract of the nut exhibits direct vasoconstriction and adrenaline potentiation in rats. Antimicrobial activity is due to polyphenolic fraction. Tannins potentiated the action of acetylcholine in ileum and uterus of rat and noradrenaline on seminal vesicle at low concentration.

Due to increased incidence of oral cancer associated with betel chewing, the use of arecanut as a masticatory is being discouraged.

Seeds are toxic at 8-10 g, fluid extract at 3.7 ml; and arecoline hydrobromide at 4.3-6.5 mg. (Francis Brinker.)

Dosage: Dried ripe fruit—1-2 g powder. (API Vol. I.)... areca catechu

A. Juss.

Synonym: Melia azadirachta Linn.

Family: Meliaceae.

Habitat: Native to Burma; found all over India.

English: Neem tree, Margosa tree.

Ayurvedic: Nimba, Nimbaka, Arishta, Arishtaphala, Pichumarda, Pichumanda, Pichumandaka, Tiktaka, Sutiktak, Paaribhadra.

Unani: Aazaad-Darakht-e-Hindi.

Siddha/Tamil: Vemmu, Veppu, Veppan, Arulundi.

Action: Leaf, bark—antimicrobial, antifungal, anthelmintic, insecti- cidal, antiviral, antipyretic, anti- malarial, antiperiodic, mosquito larvicidal, anti-inflammatory, antifertility, spermicidal, hypogly- caemic; used in inflammation of gums, gingivitis, periodonitis, sores, boils, enlargement of spleen, malarial fever, fever during childbirth, measles, smallpox, head scald and cutaneous affections. Oil—used as a contraceptive for intravaginal use, for the treatment of vaginal infections, and as a mosquito repellent.

Plant tetranortriterpenoids have been examined extensively for their antibiotic, antitumour, insecticidal, antibacterial and antifungal activities.

The methanolic extract of the bark shows antimalarial activity against Plasmodium falciparum.

The aqueous extract of leaves exhibited antiulcer and anti-inflammatory activity.

The water-soluble portion of alcoholic extract of leaves reduces blood sugar in glucose-fed and adrenaline- induced hyperglycaemic rats (but not in normal and streptozotocin-induced diabetic rats).

A volatile fraction of the Neem oil is reported to be responsible for sper- micidal activity at a dose of 25 mg/ml for human sperm. The oil has been found to retard the growth of human immunodeficiency virus.

Neem oil has caused mitochondri- al injury in mice; poisonous in high doses. (Sharon M. Herr.)

Dosage: Dried leaf—1-3 g powder; 10-20 g for decoction; stembark— 2-4 g powder decoction for external use. (API Vol. II.) Leaf juice— 10-20 ml; oil—5-10 drops; bark decoction—50-100 ml. (CCRAS.)... azadirachta indica

The o?cially approved name for a medicinal substance used in the UK. A 1992 European Union directive required the use of a Recommended International Non-proprietary Name (rINN) for these substances. Usually the BAN and rINN were identical; where there was a difference, the rINN nomenclature is now used. An exception is adrenaline, which remains the o?cial name in Europe with the rINN – epinephrine – being a synonym.... british approved names (ban)

Physical or psychological reliance on a substance or an individual. A baby is naturally dependent on its parents, but as the child develops, this dependence lessens. Some adults, however, remain partly dependent, making abnormal demands for admiration, love and help from parents, relatives and others.

The dependence that most concerns modern society is one in which individuals become dependent on or addicted to certain substances such as alcohol, drugs, tobacco (nicotine), caffeine and solvents. This is often called substance abuse. Some people become addicted to certain foods or activities: examples of the latter include gambling, computer games and use of the Internet.

The 28th report of the World Health Organisation Expert Committee on Drug Dependence in 1993 de?ned drug dependence as: ‘A cluster of physiological, behavioural and cognitive phenomena of variable intensity, in which the use of a psychoactive drug (or drugs) takes on a high priority. The necessary descriptive characteristics are preoccupation with a desire to obtain and take the drug and persistent drug-seeking behaviour. Psychological dependence occurs when the substance abuser craves the drug’s desirable effects. Physical dependence occurs when the user has to continue taking the drug to avoid distressing withdrawal or abstinence symptoms. Thus, determinants and the problematic consequences of drug dependence may be biological, psychological or social and usually interact.’

Di?erent drugs cause di?erent rates of dependence: TOBACCO is the most common substance of addiction; HEROIN and COCAINE cause high rates of addiction; whereas ALCOHOL is much lower, and CANNABIS lower again. Smoking in the western world reached a peak after World War II with almost 80 per cent of the male population smoking. The reports on the link between smoking and cancer in the early 1960s resulted in a decline that has continued so that only around a quarter of the adult populations of the UK and USA smokes. Globally, tobacco consumption continues to grow, particularly in the developing world with multinational tobacco companies marketing their products aggressively.

Accurate ?gures for illegal drug-taking are hard to obtain, but probably approximately 4 per cent of the population is dependent on alcohol and 2 per cent on other drugs, both legal and illegal, at any one time in western countries.

How does dependence occur? More than 40 distinct theories or models of drug misuse have been put forward. One is that the individual consumes drugs to cope with personal problems or diffculties in relations with others. The other main model emphasises environmental in?uences such as drug availability, environmental pressures to consume drugs, and sociocultural in?uences such as peer pressure.

By contrast to these models of why people misuse drugs, models of compulsive drug use – where individuals have a compulsive addiction

– have been amenable to testing in the laboratory. Studies at cellular and nerve-receptor levels are attempting to identify mechanisms of tolerance and dependence for several substances. Classical behaviour theory is a key model for understanding drug dependence. This and current laboratory studies are being used to explain the reinforcing nature of dependent substances and are helping to provide an explanatory framework for dependence. Drug consumption is a learned form of behaviour. Numerous investigators have used conditioning theories to study why people misuse drugs. Laboratory studies are now locating the ‘reward pathways’ in the brain for opiates and stimulants where positive reinforcing mechanisms involve particular sectors of the brain. There is a consensus among experts in addiction that addictive behaviour is amenable to e?ective treatment, and that the extent to which an addict complies with treatment makes it possible to predict a positive outcome. But there is a long way to go before the mechanisms of drug addiction are properly understood or ways of treating it generally agreed.

Effects of drugs Cannabis, derived from the plant Cannabis sativa, is a widely used recreational drug. Its two main forms are marijuana, which comes from the dried leaves, and hashish which comes from the resin. Cannabis may be used in food and drink but is usually smoked in cigarettes to induce relaxation and a feeling of well-being. Heavy use can cause apathy and vagueness and may even cause psychosis. Whether or not cannabis leads people to using harder drugs is arguable, and a national debate is underway on whether its use should be legalised for medicinal use. Cannabis may alleviate the symptoms of some disorders – for example, MULTIPLE SCLEROSIS (MS) – and there are calls to allow the substance to be classi?ed as a prescribable drug.

About one in ten of Britain’s teenagers misuses volatile substances such as toluene at some time, but only about one in 40 does so regularly. These substances are given o? by certain glues, solvents, varnishes, and liquid fuels, all of which can be bought cheaply in shops, although their sale to children under 16 is illegal. They are often inhaled from plastic bags held over the nose and mouth. Central-nervous-system excitation, with euphoria and disinhibition, is followed by depression and lethargy. Unpleasant effects include facial rash, nausea and vomiting, tremor, dizziness, and clumsiness. Death from COMA and acute cardiac toxicity is a serious risk. Chronic heavy use can cause peripheral neuropathy and irreversible cerebellar damage. (See SOLVENT ABUSE (MISUSE).)

The hallucinogenic or psychedelic drugs include LYSERGIC ACID DIETHYLAMIDE (LSD) or acid, magic mushrooms, ecstasy (MDMA), and phencyclidine (PCP or ‘angel’ dust, mainly used in the USA). These drugs have no medicinal uses. Taken by mouth, they produce vivid ‘trips’, with heightened emotions and perceptions and sometimes with hallucinations. They are not physically addictive but can cause nightmarish bad trips during use and ?ashbacks (vivid reruns of trips) after use, and can probably trigger psychosis and even death, especially if drugs are mixed or taken with alcohol.

Stimulant drugs such as amphetamine and cocaine act like adrenaline and speed up the central nervous system, making the user feel con?dent, energetic, and powerful for several hours. They can also cause severe insomnia, anxiety, paranoia, psychosis, and even sudden death due to convulsions or tachycardia. Depression may occur on withdrawal of these drugs, and in some users this is su?ciently deterrent to cause psychological dependence. Amphetamine (‘speed’) is mainly synthesised illegally and may be eaten, sni?ed, or injected. Related drugs, such as dexamphetamine sulphate (Dexedrine), are prescribed pills that enter the black market. ECSTASY is another amphetamine derivative that has become a popular recreational drug; it may have fatal allergic effects. Cocaine and related drugs are used in medicine as local anaesthetics. Illegal supplies of cocaine (‘snow’ or ‘ice’) and its derivative, ‘crack’, come mainly from South America, where they are made from the plant Erythroxylon coca. Cocaine is usually sni?ed (‘snorted’) or rubbed into the gums; crack is burnt and inhaled.

Opiate drugs are derived from the opium poppy, Papaver somniferum. They are described as narcotic because they induce sleep. Their main medical use is as potent oral or injectable analgesics such as MORPHINE, DIAMORPHINE, PETHIDINE HYDROCHLORIDE, and CODEINE. The commonest illegal opiate is heroin, a powdered form of diamorphine that may be smoked, sni?ed, or injected to induce euphoria and drowsiness. Regular opiate misuse leads to tolerance (the need to take ever larger doses to achieve the same e?ect) and marked dependence. A less addictive oral opiate, METHADONE HYDROCHLORIDE, can be prescribed as a substitute that is easier to withdraw.

Some 75,000–150,000 Britons now misuse opiates and other drugs intravenously, and pose a huge public-health problem because injections with shared dirty needles can carry the blood-borne viruses that cause AIDS/HIV and HEPATITIS B. Many clinics now operate schemes to exchange old needles for clean ones, free of charge. Many addicts are often socially disruptive.

For help and advice see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP – National Dugs Helpline.

(See ALCOHOL and TOBACCO for detailed entries on those subjects.)... dependence

Organs whose function it is to secrete into the blood or lymph, substances known as HORMONES. These play an important part in general changes to or the activities of other organs at a distance. Various diseases arise as the result of defects or excess in the internal secretions of the di?erent glands. The chief endocrine glands are:

Adrenal glands These two glands, also known as suprarenal glands, lie immediately above the kidneys. The central or medullary portion of the glands forms the secretions known as ADRENALINE (or epinephrine) and NORADRENALINE. Adrenaline acts upon structures innervated by sympathetic nerves. Brie?y, the blood vessels of the skin and of the abdominal viscera (except the intestines) are constricted, and at the same time the arteries of the muscles and the coronary arteries are dilated; systolic blood pressure rises; blood sugar increases; the metabolic rate rises; muscle fatigue is diminished. The super?cial or cortical part of the glands produces steroid-based substances such as aldosterone, cortisone, hydrocortisone, and deoxycortone acetate, for the maintenance of life. It is the absence of these substances, due to atrophy or destruction of the suprarenal cortex, that is responsible for the condition known as ADDISON’S DISEASE. (See CORTICOSTEROIDS.)

Ovaries and testicles The ovary (see OVARIES) secretes at least two hormones – known, respectively, as oestradiol (follicular hormone) and progesterone (corpus luteum hormone). Oestradiol develops (under the stimulus of the anterior pituitary lobe – see PITUITARY GLAND below, and under separate entry) each time an ovum in the ovary becomes mature, and causes extensive proliferation of the ENDOMETRIUM lining the UTERUS, a stage ending with shedding of the ovum about 14 days before the onset of MENSTRUATION. The corpus luteum, which then forms, secretes both progesterone and oestradiol. Progesterone brings about great activity of the glands in the endometrium. The uterus is now ready to receive the ovum if it is fertilised. If fertilisation does not occur, the corpus luteum degenerates, the hormones cease acting, and menstruation takes place.

The hormone secreted by the testicles (see TESTICLE) is known as TESTOSTERONE. It is responsible for the growth of the male secondary sex characteristics.

Pancreas This gland is situated in the upper part of the abdomen and, in addition to the digestive enzymes, it produces INSULIN within specialised cells (islets of Langerhans). This controls carbohydrate metabolism; faulty or absent insulin production causes DIABETES MELLITUS.

Parathyroid glands These are four minute glands lying at the side of, or behind, the thyroid (see below). They have a certain e?ect in controlling the absorption of calcium salts by the bones and other tissues. When their secretion is defective, TETANY occurs.

Pituitary gland This gland is attached to the base of the brain and rests in a hollow on the base of the skull. It is the most important of all endocrine glands and consists of two embryologically and functionally distinct lobes.

The function of the anterior lobe depends on the secretion by the HYPOTHALAMUS of certain ‘neuro-hormones’ which control the secretion of the pituitary trophic hormones. The hypothalamic centres involved in the control of speci?c pituitary hormones appear to be anatomically separate. Through the pituitary trophic hormones the activity of the thyroid, adrenal cortex and the sex glands is controlled. The anterior pituitary and the target glands are linked through a feedback control cycle. The liberation of trophic hormones is inhibited by a rising concentration of the circulating hormone of the target gland, and stimulated by a fall in its concentration. Six trophic (polypeptide) hormones are formed by the anterior pituitary. Growth hormone (GH) and prolactin are simple proteins formed in the acidophil cells. Follicle-stimulating hormone (FSH), luteinising hormone (LH) and thyroid-stimulating hormone (TSH) are glycoproteins formed in the basophil cells. Adrenocorticotrophic hormone (ACTH), although a polypeptide, is derived from basophil cells.

The posterior pituitary lobe, or neurohypophysis, is closely connected with the hypothalamus by the hypothalamic-hypophyseal tracts. It is concerned with the production or storage of OXYTOCIN and vasopressin (the antidiuretic hormone).

PITUITARY HORMONES Growth hormone, gonadotrophic hormone, adrenocorticotrophic hormone and thyrotrophic hormones can be assayed in blood or urine by radio-immunoassay techniques. Growth hormone extracted from human pituitary glands obtained at autopsy was available for clinical use until 1985, when it was withdrawn as it is believed to carry the virus responsible for CREUTZFELDT-JAKOB DISEASE (COD). However, growth hormone produced by DNA recombinant techniques is now available as somatropin. Synthetic growth hormone is used to treat de?ciency of the natural hormone in children and adults, TURNER’S SYNDROME and chronic renal insu?ciency in children.

Human pituitary gonadotrophins are readily obtained from post-menopausal urine. Commercial extracts from this source are available and are e?ective for treatment of infertility due to gonadotrophin insu?ciency.

The adrenocorticotrophic hormone is extracted from animal pituitary glands and has been available therapeutically for many years. It is used as a test of adrenal function, and, under certain circumstances, in conditions for which corticosteroid therapy is indicated (see CORTICOSTEROIDS). The pharmacologically active polypeptide of ACTH has been synthesised and is called tetracosactrin. Thyrotrophic hormone is also available but it has no therapeutic application.

HYPOTHALAMIC RELEASING HORMONES which affect the release of each of the six anterior pituitary hormones have been identi?ed. Their blood levels are only one-thousandth of those of the pituitary trophic hormones. The release of thyrotrophin, adrenocorticotrophin, growth hormone, follicle-stimulating hormone and luteinising hormone is stimulated, while release of prolactin is inhibited. The structure of the releasing hormones for TSH, FSH-LH, GH and, most recently, ACTH is known and they have all been synthesised. Thyrotrophin-releasing hormone (TRH) is used as a diagnostic test of thyroid function but it has no therapeutic application. FSH-LH-releasing hormone provides a useful diagnostic test of gonadotrophin reserve in patients with pituitary disease, and is now used in the treatment of infertility and AMENORRHOEA in patients with functional hypothalamic disturbance. As this is the most common variety of secondary amenorrhoea, the potential use is great. Most cases of congenital de?ciency of GH, FSH, LH and ACTH are due to defects in the hypothalamic production of releasing hormone and are not a primary pituitary defect, so that the therapeutic implication of this synthesised group of releasing hormones is considerable.

GALACTORRHOEA is frequently due to a microadenoma (see ADENOMA) of the pituitary. DOPAMINE is the prolactin-release inhibiting hormone. Its duration of action is short so its therapeutic value is limited. However, BROMOCRIPTINE is a dopamine agonist with a more prolonged action and is e?ective treatment for galactorrhoea.

Thyroid gland The functions of the thyroid gland are controlled by the pituitary gland (see above) and the hypothalamus, situated in the brain. The thyroid, situated in the front of the neck below the LARYNX, helps to regulate the body’s METABOLISM. It comprises two lobes each side of the TRACHEA joined by an isthmus. Two types of secretory cells in the gland – follicular cells (the majority) and parafollicular cells – secrete, respectively, the iodine-containing hormones THYROXINE (T4) and TRI-IODOTHYRONINE (T3), and the hormone CALCITONIN. T3 and T4 help control metabolism and calcitonin, in conjunction with parathyroid hormone (see above), regulates the body’s calcium balance. De?ciencies in thyroid function produce HYPOTHYROIDISM and, in children, retarded development. Excess thyroid activity causes thyrotoxicosis. (See THYROID GLAND, DISEASES OF.)... endocrine glands

(Linn.) Penn.

Synonym: Herpestis monnieria (Linn.) H. B. & K. Moniera cuneifolia Michx.

Family: Scrophulariaceae.

Habitat: Throughout the plains of India in damp marshy areas.

English: Thyme-leaved Gratiola.

Ayurvedic: Braahmi, Aindri, Nir- braahmi, Kapotavankaa, Bhaarati, Darduradalaa, Matsyaakshaka, Shaaluraparni, Mandukaparni (also equated with Centella asiatica Linn., synonym Hydrocotyle asiatica Linn. Umbelliferae, Apiaceae).

Unani: Brahmi.

Siddha/Tamil: Piramivazhukkai, Neerbrami.

Folk: Jalaneem, Safed-Chammi.

Action: Adaptogenic, astringent, diuretic, sedative, potent nervine tonic, anti-anxiety agent (improves mental functions, used in insanity, epilepsy), antispasmodic (used in bronchitis, asthma and diarrhoea).

Key application: In psychic disorders and as a brain tonic. (The Ayurvedic Pharmacopoeia of India; Indian Herbal Pharmacopoeia.)

B. monnieri has been shown to cause prolonged elevated level of cerebral glutamic acid and a transient increase in GABA level. It is assumed that endogenous increase in brain glutamine maybe helpful in the process oflearn- ing.

The herb contains the alkaloids brahmine, herpestine, and a mixture of three bases. Brahmine is highly toxic; in therapeutic doses it resembles strychnine. The herb also contains the saponins, monnierin, hersaponin, bacosides A and B. Bacosides A and B possess haemolytic activity. Her- saponin is reported to possess car- diotonic and sedative properties. It was found, as in case of reserpene, to deplete nor-adrenaline and 5-HT content of the rat brain.

An alcoholic extract of the plant in a dose of 50 mg/kg produced tranquil- izing effect on albino rats and dogs, but the action was weaker than that produced by chlorpromazine.

Dosage: Whole plant—1-3 g powder. (API Vol. II.)... bacopa monnieri

A group of disorders of the eye characterised by the intraocular pressure being so high as to damage the nerve ?bres in the retina and the optic nerve (see EYE) as it leaves the eye en route to the brain. The affected person suffers limitation of the ?eld of vision and on examination the optic disc can be seen to be cupped. The clinical signs depend on the rate and extent of rise in pressure.

Individuals most at risk have a family history of GLAUCOMA (especially among siblings), are myopic (short-sighted), or have diabetic or thyroid eye disease. People with a strong family history of the disease should have regular eye checks, including tonometry, from the age of 35 years.

Glaucoma is usually classi?ed as being either open-angle glaucoma or narrow-angle glaucoma.

Open-angle glaucoma is a chronic, slowly progressive, usually bilateral disorder. It occurs in one in 200 of people over 40 and accounts for 20 per cent of those registered blind in Great Britain. Symptoms are virtually non-existent until well into the disease, when the patient may experience visual problems. It is not painful. The characteristic ?ndings are that the intraocular pressure is raised (normal pressure is up to 21 mm Hg) causing cupping of the optic disc and a glaucomatous visual-?eld loss. The angle between the iris and the cornea remains open. Treatment is aimed at decreasing the intraocular pressure initially by drops, tablets and intravenous drug administration. Surgery may be required later. A trabeculectomy is an operation to create a channel through which ?uid can drain from the eye in a controlled fashion in order to bring the pressure down.

Narrow-angle glaucoma affects one in 1,000 people over 40 years of age and is more common in women. Symptoms may start with coloured haloes around street lights at night. These may then be followed by rapid onset of severe pain in and around the eye accompanied by a rapid fall in vision. One eye is usually affected ?rst; this alerts the surgeon so that action can be taken to prevent a similar attack in the other eye. Treatment must be started as an emergency with a topical beta blocker (see BETA-ADRENOCEPTOR-BLOCKING DRUGS) in eye drops with other drugs such as ADRENALINE or pilocarpine added as necessary. Dorzolamide, a topical anhydrase inhibitor, can also be used. ACETAZOLAMIDE, also an anhydrase inhibitor, can be given by mouth. In an emergency before surgery, MANNITOL can be given through an intravenous infusion; this is followed by surgery to prevent recurrence. Acute narrow-angle glaucoma occurs because the peripheral iris is pushed against the back of the cornea. This closes o? the angle between iris and cornea through which aqueous humour drains out of the eye. Since the aqueous humour cannot drain away, it builds up inside the eye causing a rapid increase in pressure.

Various types of LASER treatment – trabeculoplasty (‘burning’ the trabecular network); iridotomy (cutting holes to relieve pressure); and ciliary-body ablation by ‘burning’ – are sometimes used in preference to surgery.... glaucoma

This is transmitted chemically, by the formation at nerve-endings of chemical substances. When, for example, a NERVE to a muscle is stimulated, there appears at the NEUROMUSCULAR JUNCTION the chemical substance, ACETYLCHOLINE. Acetylcholine also appears at endings of the parasympathetic nerves (see NERVOUS SYSTEM) and transmits the e?ect of the parasympathetic impulse. When an impulse passes down a sympathetic nerve, the e?ect of it is transmitted at the nerve-ending by the chemical liberated there: ADRENALINE or an adrenaline-like substance.... nervous impulse

Also called beta blockers, these drugs interrupt the transmission of neuronal messages via the body’s adrenergic receptor sites. In the HEART these are called beta1 (cardioselective) receptors. Another type – beta2 (non-cardioselective) receptors – is sited in the airways, blood vessels, and organs such as the eye, liver and pancreas. Cardioselective beta blockers act primarily on beta1 receptors, whereas non-cardioselective drugs act on both varieties, beta1 and beta2. (The neurotransmissions interrupted at the beta-receptor sites through the body by the beta blockers are initiated in the ADRENAL GLANDS: this is why these drugs are sometimes described as beta-adrenergic-blocking agents.)

They work by blocking the stimulation of beta adrenergic receptors by the neurotransmitters adrenaline and noradrenaline, which are produced at the nerve endings of that part of the SYMPATHETIC NERVOUS SYSTEM – the autonomous (involuntary) network

– which facilitates the body’s reaction to anxiety, stress and exercise – the ‘fear and ?ight’ response.

Beta1 blockers reduce the frequency and force of the heartbeat; beta2 blockers prevent vasodilation (increase in the diameter of blood vessels), thus in?uencing the patient’s blood pressure. Beta1 blockers also affect blood pressure, but the mechanism of their action is unclear. They can reduce to normal an abnormally fast heart rate so the power of the heart can be concomitantly controlled: this reduces the oxygen requirements of the heart with an advantageous knock-on e?ect on the respiratory system. These are valuable therapeutic effects in patients with ANGINA or who have had a myocardial infarction (heart attack – see HEART, DISEASES OF), or who suffer from HYPERTENSION. Beta2 blockers reduce tremors in muscles elsewhere in the body which are a feature of anxiety or the result of thyrotoxicosis (an overactive thyroid gland – see under THYROID GLAND, DISEASES OF). Noncardioselective blockers also reduce the abnormal pressure caused by the increase in the ?uid in the eyeball that characterises GLAUCOMA.

Many beta-blocking drugs are now available; minor therapeutic di?erences between them may in?uence the choice of a drug for a particular patient. Among the common drugs are:

Primarily cardioselective	Non-cardioselective
Acebutolol	Labetalol
Atenolol	Nadolol
Betaxolol	Oxprenolol
Celiprolol	Propanolol
Metoprolol	Timolol

These powerful drugs have various side-effects and should be prescribed and monitored with care. In particular, people who suffer from asthma, bronchitis or other respiratory problems may develop breathing diffculties. Long-term treatment with beta blockers should not be suddenly stopped, as this may precipitate a severe recurrence of the patient’s symptoms – including, possibly, a sharp rise in blood pressure. Gradual withdrawal of medication should mitigate untoward effects.... beta-adrenoceptor-blocking drugs

Stapf.

Family: Rutaceae.

Habitat: Native to tropical America; cultivated in Indian gardens.

Family: Umbelliferae; Apiaceae.

Habitat: Native to the Mediterranean region; cultivated in Uttar Pradesh., Punjab, Assam and Orissa.

English: Anise, Aniseed.

Unani: Anisoon, Baadiyaan-roomi.

Action: Carminative, diuretic, anticholerin, antispasmodic, expectorant. Used for flatulence, dry coughs, whooping cough, bronchitis.

Key application: Internally in dyspeptic complaints; internally and externally in catarrhs of the respiratory tract. (German Commission E, ESCOP, WHO, The British Herbal Pharmacopoeia.)

The fruit gave volatile oil consisting mainly of trans-anethole (70-90%), with estragole, anise ketone, anisic acid, beta-caryophyllene, anisaldehyde, linalool. The fruit contained traces of furocoumarins; seeds gave benzoic acid, caffeic acid, containing protein and myristicin. Roots afforded sterols, coumarins and flavone glyco- sides. Aniseed has been demonstrated to increase the mucociliary transport in vitro and to significantly increase liver-regeneration in rats.

Aniseed is also used as a galacta- gogue. This property is thought due to the presence of polymers of anethole, dianethole and photoanethole.

Aqueous extract of roasted aniseed is reported to show cholinomimetic effect on rat blood pressure, rat jejunum and frog rectus abdominis preparations.

Alcoholic extract of aniseeds possesses antimicrobial and fungicidal activity.

Anethole has a structure similar to catecholamines including adrenaline, noradrenaline and dopamine and to the hallucinogenic compound myris- ticin as well. (Natural Medicines Comprehensive Database, 2007.)... pilocarpus microphyllus

Animal bites are best treated as puncture wounds and simply washed and dressed. In some cases ANTIBIOTICS may be given to minimise the risk of infection, together with TETANUS toxoid if appropriate. Should RABIES be a possibility, then further treatment must be considered. Bites and stings of venomous reptiles, amphibians, scorpions, snakes, spiders, insects and ?sh may result in clinical effects characteristic of that particular poisoning. In some cases speci?c ANTIVENOM may be administered to reduce morbidity and mortality.

Many snakes are non-venomous (e.g. pythons, garter snakes, king snakes, boa constrictors) but may still in?ict painful bites and cause local swelling. Most venomous snakes belong to the viper and cobra families and are common in Asia, Africa, Australia and South America. Victims of bites may experience various effects including swelling, PARALYSIS of the bitten area, blood-clotting defects, PALPITATION, respiratory di?culty, CONVULSIONS and other neurotoxic and cardiac effects. Victims should be treated as for SHOCK – that is, kept at rest, kept warm, and given oxygen if required but nothing by mouth. The bite site should be immobilised but a TOURNIQUET must not be used. All victims require prompt transfer to a medical facility. When appropriate and available, antivenoms should be administered as soon as possible.

Similar management is appropriate for bites and stings by spiders, scorpions, sea-snakes, venomous ?sh and other marine animals and insects.

Bites and stings in the UK The adder (Vipera berus) is the only venomous snake native to Britain; it is a timid animal that bites only when provoked. Fatal cases are rare, with only 14 deaths recorded in the UK since 1876, the last of these in 1975. Adder bites may result in marked swelling, weakness, collapse, shock, and in severe cases HYPOTENSION, non-speci?c changes in the electrocardiogram and peripheral leucocytosis. Victims of adder bites should be transferred to hospital even if asymptomatic, with the affected limb being immobilised and the bite site left alone. Local incisions, suction, tourniquets, ice packs or permanganate must not be used. Hospital management may include use of a speci?c antivenom, Zagreb®.

The weever ?sh is found in the coastal waters of the British Isles, Europe, the eastern Atlantic, and the Mediterranean Sea. It possesses venomous spines in its dorsal ?n. Stings and envenomation commonly occur when an individual treads on the ?sh. The victim may experience a localised but increasing pain over two hours. As the venom is heat-labile, immersion of the affected area in water at approximately 40 °C or as hot as can be tolerated for 30 minutes should ease the pain. Cold applications will worsen the discomfort. Simple ANALGESICS and ANTIHISTAMINE DRUGS may be given.

Bees, wasps and hornets are insects of the order Hymenoptera and the females possess stinging apparatus at the end of the abdomen. Stings may cause local pain and swelling but rarely cause severe toxicity. Anaphylactic (see ANAPHYLAXIS) reactions can occur in sensitive individuals; these may be fatal. Deaths caused by upper-airway blockage as a result of stings in the mouth or neck regions are reported. In victims of stings, the stinger should be removed as quickly as possible by ?icking, scraping or pulling. The site should be cleaned. Antihistamines and cold applications may bring relief. For anaphylactic reactions ADRENALINE, by intramuscular injection, may be required.... bites and stings

Linn.

Family: Portulacaceae.

Habitat: All over India, cultivated as a vegetable.

English: Common Purslane.

Ayurvedic: Brihat Lonikaa, Lonaa, Loni, Ghoddhika, Ghotikaa, Upodika, Khursaa.

Unani: Khurfaa, Kulfaa.

Siddha/Tamil: Pulli-keerai, Parup- pukirai.

Action: Refrigerant (reduces body heat), mild spasmodic, diuretic, antiscorbutic. Used in scurvy and in diseases of liver, spleen, kidney and bladder; also in dysuria, stomatitis and dysentery. A paste of leaves is applied to swellings, erysipelas, burns and scalds. Seeds—diuretic, antidysenteric; applied externally to burns and scalds.

A crude protein-free extract of the herb contained l-nor-adrenaline, do- pamine and l-dopa, also catechol. (The fresh plant contained 2.5 mg/g l-nor- adrenaline in one sample.) The extract gave a strong pressor response when injected intravenously into anaesthetized dogs.

The oral administration of the ho- mogenates of P. oleracea reduced the blood sugar level of alloxan-diabetic rabbits to normal.

The extract of the leaves and stems reduced muscle tone in individuals suffering from spasticity and exhibited skeletal muscle relaxant activity both in vitro and in vivo. The extract produced dose-dependent negative in- otropic and chronotropic effects and pressor response on rat blood pressure.

The diuretic action of the herb is attributed to the presence of high percentage of potassium salts.

Dosage: Plant-125-400 mg powder; juice—1-20 ml (CCRAS.)... portulaca oleracea

These drugs temporarily raise the BLOOD PRESSURE by constricting peripheral blood vessels. Sometimes they are used as a speedy way of raising blood pressure when other treatment has failed. EPHEDRINE and methoxamine hydrochloride are examples of this type of sympathomimetic.

Cardiopulmonary resuscitation ADRENALINE (epinephrine) is given intravenously in cardiac arrest, and other drugs used include ATROPINE and CALCIUM.... vasoconstrictor sympathomimetics

Vasoconstrictor sympathomimetic drugs, such as EPHEDRINE and NORADRENALINE, raise the BLOOD PRESSURE temporarily by acting on receptors that constrict peripheral blood vessels. They are occasionally used as a quick way of raising blood pressure when other measures have failed, but they have potentially serious side-effects on the kidney. Vasoconstrictors are also used with local anaesthetics (see under ANAESTHESIA) to counteract the latter’s vasodilator e?ect. Adrenaline will reduce local blood ?ow, slow the absorption of anaesthetic and prolong its e?ect.... vasoconstrictors

Cancerous or noncancerous tumours in the adrenal glands, usually causing excess secretion of hormones. Adrenal tumours are rare. Tumours of the adrenal cortex may secrete aldosterone, causing primary aldosteronism, or hydrocortisone, causing Cushing’s syndrome. Tumours of the medulla may cause excess secretion of adrenaline and noradrenaline. Two types of tumour affect the medulla: phaeochromocytoma and neuroblastoma, which affects children. These tumours cause intermittent hypertension and sweating attacks. Surgical removal of a tumour usually cures these conditions.... adrenal tumours

Gaertn.

Synonym: Phyllanthus emblica Linn.

Family: Euphorbiaceae.

Habitat: Native to tropical Southeast Asia; distributed throughout India; also planted in public parks.

English: Emblic, Indian gooseberry.

Ayurvedic: Aaamalaki, Aaamalaka, Dhaatri, Kaayasthaa, Amoghaa, Amritaphala, Amla, Aaamalaa, Dhaatriphala, Vayasyaa, Vrshya, Shiva, Hattha.

Unani: Aamalaa, Amlaj.

Siddha/Tamil: Nellikkaai, Nelli.

Action: Fruit—antianaemic, anabolic, antiemetic, bechic, astringent, antihaemorrhagic, antidiarrhoeal, diuretic, antidiabetic, carminative, antioxidant. Used in jaundice, dyspepsia, bacillary dysentery, eye trouble and as a gastrointestinal tonic. Juice with turmeric powder and honey is prescribed in diabetes insipidus. Seed—antibilious, antiasthmatic. Used in bronchitis. Bark—astringent. Leaf—juice is given in vomiting.

A decoction of powdered pericarp is prescribed for paptic ulcer.

Key application: As an antacid. (Indian Herbal Pharmacopoeia.).

The fruit is an important source of vitamin C, minerals and amino acids. The edible fruit tissue contains protein concentration threefold and vitamin C (ascorbic acid) concentration 160-fold than those of apple. The fruit also contains considerably higher concentration of most minerals and amino acids than apple.

The fruit gave cytokinine-like substances identified as zeatin, zeatin ribo- side and zeatin nucleotide; suspension culture gave phyllembin. Phyllem- bin exhibits CNS depressant and spasmolytic activity, potentiates action of adrenaline and hypnotic action of Nembutal.

The leaves contain gallic acid (10.8 mg/g dry basis), besides ascorbic and music acid. The methanol extract of the leaves is found to be effective in rat paw inflammation.

The bark contains tannin identified as mixed type of proanthocyanidin.

The fruit contains superoxide dis- mutase 482.14 units/g fresh weight and exhibits antisenescent (anti-aging) activity. Fruit, juice, its sediment and residue are antioxidant due to gallic acid. EtOH (50%) extract—antiviral.

Aqueous extract of the fruit increases cardiac glycogen level and decreases serum GOT, GPT and LDH in rats having induced myocardial necrosis.

Preliminary evidence suggests that the fruit and its juice may lower serum cholesterol, LDL, triglycerides and phospholipids without affecting HDL levels and may have positive effect on atherosclerosis. (Eur J clin Nutr, 42, 1988, 939-944; PhytotherRes, 14, 2000, 592-595.)

An aqueous extract of the fruit has been reported to provide protection against radiation-induced chromosomal damage in both pre-and postirradiation treatment. The fruit is reported to enhance natural killer cell activity and antibody dependent cellular cytotoxicity in mice bearing Dalton's lymphoma ascites tumour. The extract of the fruit and ascorbic acid prevented hepatotoxic and nephrotoxic effects induced by lead and aluminium. The toxicity could be counteracted to a great extent by the fruit extract than by an amount of ascorbic acid alone equivalent to that contained in fruits. (The fruit can be used as a dietary supplement to counteract prolonged exposure to metals in population in industrial areas.)

The fruits are reported to activate trypsin (proteolytic enzyme) activity.

The fruits can be used as coagulant in the treatment of water and can purify low turbidity water.

The fruits can be consumed safely all round the year.

Dosage: Fresh fruit—10-20 g; pulp juice—5-10 ml. (API Vol. I.)... emblica officinalis

(L.) Gaertn.

Habitat: Western Himalayas at 1,800 and Kashmir at 2,400 m, also grown in gardens.

English: Holy Thistle, Milk Thistle.

Action: Seeds—liver protective, gallbladder protective, antioxidant. Used in jaundice and other biliary affections, intermittent fevers, uterine trouble, also as a galactagogue. Alcoholic extract used for haemorrhoids and as a general substitute for adrenaline. Seeds are used for controlling haemorrhages. Leaves—sudorific and aperient. Young leaves and flowering heads are consumed by diabetics.

Key application: In dyspeptic complaints. As an ingredient of formulations for toxic liver damage; chronic inflammatory liver disease and hepatic cirrhosis induced by alcohol, drugs or toxins. (Expanded Commission E Monographs, WHO.)

The seeds gave silymarin (flavanol lignin mixture), composed mainly of silybin A, silybin B (mixture known as silibinin), with isosilybin A, isosilybin B, silychristin, silydianin. In Germany, Milk Thistle has been used extensively for liver diseases and jaundice. Sily- marin has been shown conclusively to exert an antihepatotoxic effect in animals against a variety of toxins, particularly those of death cap mushroom, Amanita phalloides. Silybin, when given by intravenous injection to human patients up to 48 hours after ingestion of the death cap, was found to be highly effective in preventing fatalities.

Silymarin has been used successfully to treat patients with chronic hepatitis and cirrhosis; it is active against hepatitis B virus, and lowers fat deposits in the liver in animals.

(For hepatic cirrhosis: 420 mg per day; for chronic active hepatitis 240 mg twice daily—extract containing 7080% silimarin.)... silybum marianum

A rare, life-threatening allergic reaction that occurs in people with an extreme sensitivity to a particular substance (allergen), often insect venom, a food item, or a drug (see allergy). When the allergen enters the bloodstream, massive amounts of histamine and other chemicals are released, causing sudden, severe lowering of blood pressure and constriction of the airways. Other symptoms may include abdominal pain, diarrhoea, swelling of the tongue and throat, and itchy rash.

Anaphylactic shock requires emergency medical treatment. An injection of

adrenaline may be life-saving. Antihistamine drugs and corticosteroid drugs may also be given.... anaphylactic shock

Arousal of the sympathetic part of the autonomic nervous system in response to fear but which also occurs in anxiety disorders. Adrenaline (epinephrine), noradrenaline (norepinephrine), and other hormones are released from the adrenal glands and nervous system, leading to a raised heart-rate, pupil dilation, and increased blood flow to the muscles. These effects make the body more efficient in either fighting or fleeing the apparent danger.... fight-or-flight response

Taken at face value, the term ‘psychosomatic’ simply means the interaction of psyche (mind) and soma (body). As such it is a noncontroversial concept that points out the many ways in which psychological factors affect the expression of physical disorder and vice-versa. Few doubt that stress makes many physical illnesses worse, at least as far as symptoms are concerned. There are also few physical illnesses in which the outcome is not made worse by psychological factors: depression after a heart attack, for example, has a worse e?ect on prognosis than even smoking. A little more problematic is the very popular belief that stress causes relapses of physical disorders, such as cancer; some studies have found this to be the case, others not.

However, calling a condition psychosomatic implies something more – the primacy of the psyche over the soma. Going back to the in?uential theories and practice of PSYCHOANALYSIS as expounded from the 1930s, many diseases have been proposed as the result of psychological factors.These have included PEPTIC ULCER, ULCERATIVE COLITIS, ASTHMA, PSORIASIS and others. In this view, much physical disorder is due to repressed or excessive emotions. Likewise it is also argued that whereas some people express psychological distress via psychological symptoms (such as anxiety, depression and so on), others develop physical symptoms instead – and that they are also at greater risk of physical disease.

The trouble with this view is that medical advances repeatedly show that it goes too far. Stress certainly causes physical symptoms – for example, DYSPEPSIA – but the belief that it caused peptic ulcers vanished with the discovery of the true cause: colonisation of the stomach by the bacterium, Helicobacter pylori. Of course, stress and social adversity affect the risk of many diseases. For example, the incidence of heart disease among UK government employees (civil servants) has been shown to be in?uenced by their social class and their degree of job satisfaction. But we do not know how this works. Some argue that social adversity and stress in?uence how the heart functions (‘He died of a broken heart’). Stress can also affect IMMUNITY but it cannot cause AIDS/HIV and we do not know if there is a link running from stress to abnormal immune function to actual illness.

We can say that psychological factors provoke physical symptoms, and often even explain how this can happen. For example, when you are anxious you produce more epinephrine (adrenaline), which gives rise to chest pain, ‘butter?ies in the stomach’ and PALPITATION. These symptoms are not ‘all in the mind’, even if the trigger is a psychological one. People who are depressed are more likely to experience nearly every physical symptom there is, but especially pain and fatigue. Taken as a whole, psychologically induced symptoms are an enormous burden on the NHS and probably responsible for more doctor visits and sickness absence than any other single cause. Also we can be con?dent that social adversity and stress powerfully in?uence the outcome of many illnesses; likewise, a vast range of unhealthy activities and behaviours such as smoking, excessive alcohol intake, excessive eating, and so on. But we must be careful not to assume that our emotions directly cause our illnesses.... psychosomatic diseases

The rash produced by the sudden release of HISTAMINE in the skin. It is characterised by acute itching, redness and wealing which subsides within a few minutes or may persist for a day or more. Depending upon the cause, it may be localised or widespread and transient or constantly recurrent over years. It has many causes.

External injuries to the skin such as the sting of a nettle (‘nettle-rash’) or an insect bite cause histamine release from MAST CELLS in the skin directly. Certain drugs, especially MORPHINE, CODEINE and ASPIRIN, can have the same e?ect. In other cases, histamine release is caused by an allergic mechanism, mediated by ANTIBODIES of the immunoglobulin E (IgE) class – see IMMUNOGLOBULINS. Thus many foods, food additives and drugs (such as PENICILLIN) can cause urticaria. Massive release of histamine may affect mucous membranes – namely the tongue or throat – and can cause HYPOTENSION and anaphylactic shock (see ANAPHYLAXIS) which can occasionally be fatal.

Physical factors can cause urticaria. Heat, exercise and emotional stress may induce a singular pattern with small pinhead weals, but widespread ?ares of ERYTHEMA, activated via the AUTONOMIC NERVOUS SYSTEM (CHOLINERGIC urticaria) may also occur.

Rarely, exposure to cold may have a smiilar e?ect (‘cold urticaria’) and anaphylactic shock following a dive into cold water in winter is occasionally fatal. The diagnosis of cold urticaria can be con?rmed by applying a block of ice to the arm which quickly induces a local weal.

Transient urticaria due to rubbing or even stroking the skin is common in young adults (DERMOGRAPHISM or factitious urticaria). More prolonged deep pressure induces delayed urticaria in other subjects. IgE-mediated urticaria is part of the atopic spectrum (see ATOPY, and SKIN, DISEASES OF – Dermatitis and eczema). Allergy to peanuts is particularly dangerous in young atopic subjects. Notwithstanding the many known causes, chronic urticaria of unknown cause is common and may have an autoimmune basis (see AUTOIMMUNE DISORDERS).

Treatment Causative factors must be removed. Topical therapy is ine?ective except for the use of calamine lotion, which reduces itching by cooling the skin. Oral ANTIHISTAMINES are the mainstay of treatment and are remarkably safe. Rarely, injection of ADRENALINE is needed as emergency treatment of massive urticaria, especially if the tongue and throat are involved, following by a short course of the oral steroid, prednisolone.

Angio-oedema is a variant of urticaria where massive OEDEMA involves subcutaneous tissues rather than the skin. It may have many causes but bee and wasp stings in sensitised subjects are particularly dangerous. There is also a rare hereditary form of angio-oedema. Acute airway obstruction due to submucosal oedema of the tongue or larynx is best treated with immediate intramuscular adrenaline and antihistamine. Rarely, TRACHEOSTOMY may be life-saving. Patients who have had two or more episodes can be taught self-injection with a preloaded adrenaline syringe.... urticaria

Relaxation is the word we use when we want to describe the need to loosen up from all body tensions which accumulate during the day. Since relaxation is a big subject which involves not only the headaches, but also ailments of the entire nervous system, it is best to drink a tea which specializes in nourishing the central system, such as: - Lavender Tea - Chamomile Tea - St. John’s Wort Tea - Kava Tea. How Teas for Relaxing Work Thanks to their great alkaline level and their great amount of natural enzymes, these Teas for Relaxing have the opposite effect of those teas that are able to give you an energy boost. Unlike those, Teas for Relaxation lower your energy rush and try to maintain a medium level of adrenaline. Some of them can actually help you sleep better. It’s also good to know that some of these Teas for Relaxing are also used by the pharmaceutical companies, as an adjuvant in creams and tinctures for cuts and opened wounds. Other than that, the scientists found out that these teas, when taken properly, might also fight other ailments of your digestive and nervous systems, such as diarrhea, upset stomach, nausea, migraines and severe headaches. It is said that their action envisions a wide range of health problems which can be ameliorated in time, thanks to these Teas for Relaxing active constituents. Efficient Teas for Relaxing If you’re looking for a very efficient tea to relax your body, you may want to try one of the following: - Chamomile Tea - induces a state of relaxation and well-being, having a pleasant taste and scent and it can be bought from almost any teashop or grocery store. Not only that, but it is also one hundred percent safe, so if you’re thinking about giving up on coffee and relaxing your body, just turn Chamomile Tea into your daily habit. - Mint Tea – one of the most popular Teas for Relaxing, Mint Tea is also a great help in case you’re suffering from respiratory problems or ailments of the digestive tract, such as diarrhea, upset stomach, colds or flu. - Valerian Tea – increases your endorphin level and enhances your body’s capacity to fight bacteria and microbes. Ancient Romans used it as a sedative and sleep aid. However, when taking a treatment based on Valerian Tea, make sure you don’t exceed the number of cups recommended per day in order to avoid complications. Teas you should avoid When choosing Teas for Relaxing, it’s best to avoid decoctions and other types of remedy which could bring you an energy boost, such as: - Ginger Tea - Gingko Biloba Tea - Rosehip Tea Side Effects of Teas for Relaxing If you’re not sure about any of these Teas for Relaxing, ask a specialist in order to gather more information. When taken properly, these teas have no side effects. However, if you’ve been taking one or many of them for a while and you’re experiencing some unusual reactions, talk to a doctor as soon as possible and don’t try to treat it at home! High dosages may lead to a number of complications such as nausea, vomiting, upset stomach or skin rash. Also, make sure you’re not allergic to any of these Teas for Relaxing before starting a treatment based on one of them! But if there’s nothing to interfere with your treatment and you’re willing to give herbal treatments a try, choose one of these teas and enjoy its health benefits!... teas for relaxing

Small nerve ?bres that lie upon the walls of blood vessels and connect the muscle ?bres of their middle coat with the NERVOUS SYSTEM. Through these nerves the blood vessels are retained in a state of moderate contraction. There are vasodilator nerves, through which are transmitted impulses that dilate the vessels, and, in the case of the skin vessels, produce the condition of blushing; there are also vasoconstrictor nerves which transmit impulses that constrict, or narrow, the blood vessels – as occurs on exposure to cold (see HYPOTHERMIA). Various drugs produce dilatation or contraction of the blood vessels, and several of the substances produced by ENDOCRINE GLANDS in the body have these effects: for example, ADRENALINE.... vasomotor nerves

A type of reaction caused by allergy. Angioedema is characterized by large, well-defined swellings, of sudden onset, in the skin, larynx (voicebox), and other areas.

The most common cause is a sudden allergic reaction to a food. Less commonly, it results from allergy to a drug (such as penicillin), a reaction to an insect bite or sting, or from infection, emotional stress, or exposure to animals, moulds, pollens, or cold conditions. There is also a hereditary form of the disease.

Angioedema may cause sudden difficulty in breathing, swallowing, and speaking, accompanied by swelling of the lips, face, and neck, depending on the area of the body affected. Angioedema that affects the throat and the larynx is potentially life-threatening because the swelling can block the airway, causing asphyxia.

Severe cases are treated with injections of adrenaline (epinephrine) and may require intubation (passage of a breathing tube via the mouth into the windpipe) or tracheostomy (surgical creation of a hole in the windpipe) to prevent suffocation. Corticosteroid drugs may also be given. In less severe cases, antihistamine drugs may relieve symptoms.... angioedema

A simple sugar that is naturally present in fruits and is a product of the digestion of starch and sucrose. It is the chief source of energy for the body and is carried to all tissues in the blood. The term blood sugar refers to glucose in the bloodstream.The level of glucose in the blood is normally kept fairly constant by the actions of various hormones, notably insulin, glucagon, adrenaline, corticosteroid hormones, and growth hormone. An abnormally high blood glucose level (known as hyperglycaemia) may cause glucose to be lost into the urine. An abnormally low blood glucose level is called hypoglycaemia.... glucose

The main form of carbohydrate stored in the body, found mainly in the liver and in muscles.

When there is too much glucose in the blood, the excess is converted to glycogen by the action of insulin and corticosteroid hormones.

When the blood glucose level is low, glycogen is converted back to glucose (a process regulated by adrenaline and glucagon) and released into the bloodstream.... glycogen

adj. 1. describing nerve fibres that release noradrenaline or adrenaline as a neurotransmitter. 2. describing receptors that are stimulated by noradrenaline or adrenaline. See adrenoceptor.... adrenergic

The part of the nervous system that controls the involuntary activities of a variety of body tissues. The autonomic nervous system is divided into the sympathetic and parasympathetic nervous systems.

The sympathetic nervous system comprises 2 chains of nerves that pass from the spinal cord throughout the body tissues. Into these tissues, the nerve endings release the neurotransmitters adrenaline (epinephrine) and noradrenaline (norepinephrine). The system also stimulates adrenaline release from the adrenal glands. In general, the actions of the sympathetic nervous system heighten activity in the body, quickening the heartbeat and breathing rate, widening blood vessels, and inducing sweating.

The parasympathetic nervous system is composed of a chain of nerves that passes from the brain and another that leaves the lower spinal cord. The nerves are distributed to the same tissues that are supplied by the sympathetic nerves. The parasympathetic nerves release the neurotransmitter acetylcholine, which has the opposite effect to adrenaline and noradrenaline. The parasympathetic system is mainly concerned with everyday functions such as digestion and excretion.

The 2 systems act in conjunction and normally balance each other. During exercise or at times of stress, the sympathetic system predominates, however, while during sleep the parasympathetic system exerts more control.... autonomic nervous system

A group of drugs, also known as beta-adrenergic blocking agents, prescribed principally to treat heart and circulatory disorders such as angina and hypertension. Beta-blockers block the effects of the sympathetic nervous system, which releases adrenaline (epinephrine) and noradrenaline (norepinephrine) at nerve endings that are known as beta receptors.

There are 2 types of beta receptor: beta 1 and beta 2. Beta 1 receptors are present in the heart and blood vessels, and beta 2 in the lungs. Some betablockers (such as acebutolol, atenolol, and metoprolol) are termed cardioselective and, because they act mostly on beta 1 receptors, are used mainly to treat heart disease such as angina, hypertension, and cardiac arrhythmia. The drugs are sometimes given after a myocardial infarction (heart attack) to reduce the likelihood of further damage to the heart muscle.

Other types of beta-blocker, such as oxprenolol, propranolol, and timolol, may be given to prevent migraine attacks by acting on blood vessels in the head; reduce the physical symptoms of anxiety; or control the symptoms of thyrotoxicosis. Beta-blocker drugs such as timolol are sometimes given in the

form of eye drops to treat glaucoma and work by lowering the fluid pressure in the eyeball.

Beta-blockers may reduce an individual’s capacity for strenuous exercise. The drugs may worsen the symptoms of asthma, bronchitis, or other forms of lung disease. They may also reduce the flow of blood to the limbs, causing cold hands and feet. In addition, sleep disturbance and depression can be side effects of beta-blockers.... beta-blocker drugs

A halt in the pumping action of the heart that occurs when its rhythmic muscular activity ceases. The most common cause of cardiac arrest is a myocardial infarction (heart attack). Other causes include respiratory arrest, electrical injury, loss of blood, hypothermia, drug overdose, and anaphylactic shock. Cardiac arrest causes sudden collapse, loss of consciousness, and absence of pulse and breathing.

The diagnosis is confirmed by monitoring the electrical activity of the heart by ECG.

This distinguishes between ventricular fibrillation and asystole, the 2 abnormalities of heart rhythm that cause cardiac arrest.

Ventricular fibrillation may be corrected by defibrillation.

Asystole, the complete absence of heart muscle activity, is more difficult to reverse but may respond to injection of adrenaline.... cardiac arrest

An inappropriate or exaggerated reaction of the immune system to a food. Sensitivity to cow’s milk protein is a fairly common food allergy in young children. Other foods most commonly implicated in food allergy are nuts, wheat, fish, shellfish, and eggs. Food allergy is more common in people who suffer from other forms of allergy or hypersensitivity, such as asthma, allergic rhinitis, and eczema.Immediate reactions, occurring within an hour or sometimes minutes of eating the trigger food, include lip swelling, tingling in the mouth or throat, vomiting, abdominal distension, abnormally loud bowel sounds, and diarrhoea. Some serious allergies can cause anaphylactic shock, requiring immediate self-injection with adrenaline (epinephrine). The only effective treatment for food allergy is avoidance of the offending food. (See also food intolerance.)... food allergy

(alpha-adrenergic blocker) a drug that prevents the stimulation of alpha *adrenoceptors at the nerve endings of the sympathetic nervous system by noradrenaline and adrenaline: it therefore causes relaxation of smooth muscle, including widening of arteries (vasodilatation) and a drop in blood pressure. Alpha blockers include *doxazosin, *phentolamine, *phenoxybenzamine, *indoramin, *prazosin, *alfuzosin, and *tamsulosin.... alpha blocker

n. tissue in the medulla of the *adrenal gland consisting of modified neural cells containing granules that are stained brown by chromates. Adrenaline and noradrenaline are released from the granules when the adrenal gland is stimulated by its sympathetic nerve supply. See also neurohormone.... chromaffin

n. dihydroxyphenylalanine: a physiologically important compound that forms an intermediate stage in the synthesis of catecholamines (dopamine, adrenaline, and noradrenaline) from the essential amino acid tyrosine. It also plays a role itself in the functioning of certain parts of the brain. The laevorotatory form, *levodopa, is administered for the treatment of *parkinsonism, in which there is a deficiency of the neurotransmitter *dopamine in the brain.... dopa

n. a substance that is produced in one part of the body (by an *endocrine gland, such as the thyroid, adrenal, or pituitary), passes into the bloodstream and is carried to other (distant) organs or tissues, where it acts to modify their structure or function. Examples of hormones are corticosteroids (from the adrenal cortex), adrenaline (from the adrenal medulla), androgens and oestrogens (from the testis and ovary, respectively), thyroid hormone (from the thyroid gland), and insulin (from the islets of Langerhans). The *pituitary gland secretes a variety of hormones, whose release is controlled by specific releasing hormones.... hormone

A machine that temporarily takes over the function of the heart and lungs to facilitate operations such as open heart surgery, heart transplants, and heart–lung transplants.

A heart–lung machine consists of a pump (to replace the heart’s function) and an oxygenator (to replace the lung’s function). It bypasses the heart and lungs, and the heart can be stopped.

Use of a heart–lung machine tends to damage red blood cells and to cause blood clotting. These problems can be minimized, however, by the administration of heparin, an anticoagulant drug, beforehand.heart–lung transplant A procedure in which the heart and lungs of a patient are removed, and replaced with donor organs. This surgery is used to treat diseases in which the lung damage has affected the heart, or vice versa. Such diseases include cystic fibrosis, fibrosing alveolitis, and some severe congenital heart defects (see heart disease, congenital). A heart–lung machine is used to take over the function of the patient’s heart and lungs during the operation, which is no more dangerous than a heart transplant.

heart-rate The rate at which the heart contracts to pump blood around the body. Most people have a heart-rate of between 60 and 100 beats per minute at rest. This rate tends to be faster in childhood and to slow slightly with age. Very fit people may have a resting rate below 60 beats per minute.

The heart muscle responds automatically to any increase in the amount of blood returned to it from active muscles by increasing its output. During extreme exercise, heart-rate may increase to 200 contractions per minute and the output to almost 250 ml per beat.

The heart-rate is also regulated by the autonomic nervous system. The parts of this system concerned with heart action are a nucleus of nerve cells, called the cardiac centre, in the brainstem, and 2 sets of nerves (the parasympathetic and sympathetic).

At rest, the parasympathetic nerves – particularly the vagus nerve – act on the sinoatrial node to maintain a slow heart-rate. During or in anticipation of muscular activity, this inhibition lessens and the heart-rate speeds up.

Sympathetic nerves release noradrenaline, which further increases the heart-rate and force of contraction. Sympathetic activity can be triggered by fear or anger, low blood pressure, or a reduction of oxygen in the blood.

Release of adrenaline and noradrenaline by the adrenal glands also acts to increase heart-rate.

The rate and rhythm of the heart can be measured by feeling the pulse or by listening with a stethoscope; a more accurate record is provided by an ECG.

A resting heart-rate above 100 beats per minute is termed a tachycardia, and a rate below 60 beats per minute a bradycardia. (See also arrhythmia, cardiac.)... heart–lung machine

Reactions produced by the sting of insects such as bees and wasps.

Venom injected by the insect contains inflammatory substances that cause local pain, redness, and swelling for about 48 hours. Any sting in the mouth or throat is dangerous because the swelling may obstruct breathing. About 1 person in 200 is allergic to insect venom, and a severe allergic reaction can occur, leading to anaphylactic shock. A procedure known as hyposensitization is sometimes recommended for such people.

If the symptoms of anaphylactic shock develop, it is essential to seek emergency medical treatment. Any person who is known to be hypersensitive to bee or wasp venom should obtain and carry an emergency kit for the self-injection of adrenaline (epinephrine).... insect stings

A collective term for all the chemical processes that take place in the body. It is divided into catabolism (breaking down of complex substances into simpler ones) and anabolism (building up of complex substances from simpler ones). Usually, catabolism releases energy, while anabolism uses it.

The energy needed to keep the body functioning at rest is called the basal metabolic rate (BMR). It is measured in joules (or kilocalories) per square metre of body surface per hour. The BMR increases in response to factors such as stress, fear, exertion, and illness, and is controlled principally by various hormones, such as thyroxine, adrenaline (epinephrine), and insulin. (See also metabolism, inborn errors of; metabolic disorders.)... metabolism

Smoking tobacco in the form of cigarettes or cigars, or in pipes. Over 100,000 deaths per year in the are attributed to smoking. The main harmful effects of smoking are lung cancer, bronchitis, emphysema, coronary artery disease, and peripheral vascular disease. Smoking also increases the risk of mouth cancer, lip cancer, and throat cancer (see pharynx, cancer of).

Smoking is extremely harmful during pregnancy. Babies of women who smoke are smaller and are less likely to survive than those of nonsmoking mothers. Children with parents who smoke are more likely to suffer from asthma or other respiratory diseases.

There is also evidence that passive smokers are at increased risk of tobaccorelated disorders and also suffer discomfort in the form of coughing, wheezing, and sore eyes.

Tobacco contains many toxic chemicals.

Nicotine is the substance that causes addiction to tobacco.

It acts as a tranquillizer but also stimulates the release of adrenaline into the bloodstream.

This can raise blood pressure.

Tar in tobacco produces chronic irritation of the respiratory system and is thought to be a major cause of lung cancer.

Carbon monoxide passes from the lungs into the bloodstream, where it easily combines with haemoglobin in red blood cells, interfering with oxygenation of tissues.

In the long term, persistently high levels of carbon monoxide in the blood cause hardening of the arteries, which greatly increases the risk of coronary thrombosis.... smoking

(lignocaine) n. a widely used local *anaesthetic administered by injection for minor surgery and dental procedures. For the latter it is normally used in combination with adrenaline to achieve better and longer anaesthesia. Alone or in combination with other agents, it can also be applied directly to the eye, throat, and mouth, as it is absorbed through mucous membranes, and to the skin. Lidocaine is also injected intravenously to treat conditions involving abnormal heart rhythm (ventricular arrhythmias), particularly following myocardial infarction. When used as a local anaesthetic, side-effects are uncommon.... lidocaine

metabolites of the hormones adrenaline and noradrenaline, respectively. Both hormones are released in excess from a *phaeochromocytoma, and measurement of their metabolites is the most reliable screening test for this rare but potentially lethal condition. The test is best carried out on a complete 24-hour urine collection.... metanephrine and normetanephrine

An involuntary, rhythmic, oscillating movement in the muscles of part of the body, most commonly those of the hands, feet, jaw, tongue, or head. Tremor is the result of rapidly alternating muscle contraction and relaxation. Occasional tremors are experienced by most people and are due to increased production of the hormone adrenaline (epinephrine). A slight, persistent tremor is common in elderly people.

Essential tremor, which runs in families, is a slight-to-moderate tremor that may be temporarily relieved by consuming a small amount of alcohol or by taking beta-blocker drugs.

Coarse tremor (4–5 muscle movements per second), which is present at rest but reduced during movement, is often a sign of Parkinson’s disease.

An intention tremor (tremor that is worse on movement of the affected part) may be a sign of cerebellar ataxia.

Tremor may also be caused by multiple sclerosis, Wilson’s disease, mercury poisoning, thyrotoxicosis, or hepatic encephalopathy; drugs, such as amfetamines and caffeine; and withdrawal from drugs, including alcohol.... tremor

(adrenoreceptor, adrenergic receptor) any cell *receptor that binds with the catecholamines adrenaline or noradrenaline, the neurotransmitters of the *sympathetic nervous system. There are two principal types of adrenoceptor, alpha (?) and beta (?), with various subtypes of each. Alpha adrenoceptors have a slightly higher affinity for adrenaline than for noradrenaline; they can be divided into subtypes ?1 and ?2. ?1-adrenoceptors mediate contraction of smooth muscle; in the walls of arteries, for example, their stimulation causes constriction of arteries and a rise in blood pressure. ?2-adrenoceptors occur in the presynaptic membranes of neurons in the sympathetic nervous system, where they restrict the release of catecholamines from these neurons. Beta adrenoceptors also have two subtypes. ?1-adrenoceptors have an equal affinity for adrenaline and noradrenaline and are found mainly in cardiac muscle; their stimulation causes an increase in heart rate. ?2-adrenoceptors have a slightly higher affinity for adrenaline. They mediate relaxation of smooth muscle in the blood vessels, bronchi, bladder, uterus, and other organs and thus cause widening of the airways and *vasodilatation.

Drugs that stimulate these receptors (alpha agonists and beta agonists) are described as *sympathomimetic. Drugs that block their effects are the *alpha blockers and *beta blockers.... adrenoceptor

(Somogyi effect) the phenomenon of high fasting blood-sugar levels in the morning due to an unrecognized hypoglycaemic episode during the night in a person with diabetes. The low blood sugar has resulted in an outpouring of regulatory hormones, such as adrenaline and glucagon, which have raised the blood sugar to supranormal levels by the time of waking. It is important to recognize the cause, since increasing the evening insulin dose, thinking this will bring the morning sugars down, could actually cause a more severe nocturnal hypoglycaemic attack, which the body may not be able to counteract: coma might ensue. The condition can be tested for by measuring blood sugars at the time of the assumed low level.... dawn phenomenon

a condition characterized by inappropriate and sometimes severe anxiety, without adequate cause, that lasts for at least six months. It affects about 2% of the population, women twice as often as men, and often develops in early adult life. It can, however, start at any age. There is a hereditary tendency to develop the disorder and about 25% of immediate relatives of sufferers are also affected. The disorder is thought to be caused by a disturbance of the functions of neurotransmitters, such as adrenaline or GABA, in the frontal lobes or the *limbic system of the brain. Symptoms affect all parts of the body. Palpitations, sweating, tremor, and dry mouth are core symptoms; additional symptoms include giddiness, *bruxism, restlessness, fatigability, breathlessness, lightheadedness, headaches, pins and needles, chest pain, fear of imminent death or losing control, diarrhoea, flushing, dysphagia, cramps, and muscle ache. Treatment includes *cognitive behavioural therapy and medication (*SSRIs or *SNRIs).... generalized anxiety disorder

(MAO) an enzyme that catalyses the oxidation of a large variety of monoamines, including adrenaline, noradrenaline, and serotonin. Monoamine oxidase is found in most tissues, particularly the gastrointestinal tract and nervous system, and exists in two forms in humans: monoamine oxidase A primarily breaks down noradrenaline and serotonin, whereas monoamine oxidase B primarily degrades dopamine. Drugs that act as inhibitors of monoamine oxidase A may be used in the treatment of depression (see MAO inhibitor); monoamine oxidase B inhibitors are used to treat Parkinson’s disease.... monoamine oxidase

an important member of the group of gaseous mediators, which – together with amine mediators (e.g. adrenaline, noradrenaline, histamine, acetylcholine) and lipid mediators (e.g. prostaglandins) – produce many physiological responses (e.g. smooth muscle relaxation). Nitric oxide is involved in the manifestations of sepsis and septic shock. Formula: NO.... nitric oxide

n. the name given by early physiologists to the substances released from sympathetic nerve endings, now known to be a mixture of *adrenaline and *noradrenaline.... sympathin

n. the act of vomiting fresh blood. The blood may have been swallowed (e.g. following a nosebleed or tonsillectomy) but more often arises from bleeding in the oesophagus, stomach, or duodenum. Common causes of upper gastrointestinal bleeding are *oesophageal varices or peptic ulcers. Vomited blood needs to be replaced by transfused blood. Gastroscopy may identify the source of bleeding and enables endoscopic treatments to arrest it. These include adrenaline injection, thermocoagulation with a *heater-probe or by *argon plasma coagulation, band ligation of oesophageal varices, glue injection for gastric varices, and the placement of metallic clips (endoclips) on bleeding vessels.... haematemesis