Drugs Health Dictionary

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Drugs: From 1 Different Sources

These are natural products or synthetic chemicals that can alter the way in which the body works, or be used to prevent or treat disease. One or more drugs, combined with stabilisers, colourings, and other ingredients, make(s) up a medicine for practical use in treating patients. (See DEPENDENCE; MEDICINES.) In Britain, the supply of drugs is controlled by the Medicines Act. Some drugs are available only on prescription; some both on prescription and over the counter; and some are not available on NHS prescription. When enquiring about drugs that a patient is taking, it is essential to ask about all items bought over the counter and any herbal or traditional remedies that might be used, as these can interact with other prescribed drugs (see DRUG INTERACTIONS) or affect the patient’s presenting complaints. Each drug has a single generic name, but many will also have several proprietary (brand) names. It is often much cheaper to prescribe the generic form of a drug, and many doctors do so. Many hospitals and general practices in the United Kingdom now provide a list of suggested drugs for doctors to prescribe. If a doctor wishes to use a drug not on the list, he or she must give a valid reason.

Prescriptions for drugs should be printed or written clearly in ink and signed and dated by the prescriber (computer-generated facsimile signatures do not meet legal requirements). They should include the patient’s name, address and age (obligatory for children under 12), the name of the drug to be supplied, the dose and dose frequency, and the total quantity to be supplied. Any special instructions (e.g. ‘after food’) should be stated. There are special regulations about the prescription of drugs controlled under the Misuse of Drugs Regulations 1985 (see CONTROLLED DRUGS). A pharmacist can advise about which drugs are available without prescription, and is able to recommend treatment for many minor complaints. Information about exemption from prescription charges in the NHS can be obtained from health visitors, general practitioners, or social security o?ces.

Health Source: Medical Dictionary
Author: Health Dictionary

Antihypertensive Drugs

A group of drugs used to treat high blood pressure (HYPERTENSION). Untreated hypertension leads to STROKE, heart attacks and heart failure. The high incidence of hypertension in western countries has led to intensive research to discover antihypertensive drugs, and many have been marketed. The drugs may work by reducing the power of the heartbeat, by dilating the blood vessels or by increasing the excretion of salts and water in the urine (diuresis). Antihypertensive treatment has greatly improved the prognosis of patients with high blood pressure by cutting the frequency of heart and renal failure (see KIDNEYS, DISEASES OF), stroke, and coronary thrombosis (see HEART, DISEASES OF). Drugs used for treatment can be classi?ed as follows: diuretics; vasodilator antihypertensives; centrally acting antihypertensives; adrenergic neurone-blocking drugs; alpha-adrenoreceptorblocking drugs; drugs affecting the renin-angiotensin system; ganglion-blocking drugs; and tyrosine hydroxylase inhibitors. The drugs prescribed depend on many factors, including the type of hypertension being treated. Treatment can be di?cult because of the need to balance the e?ectiveness of a drug in reducing blood pressure against its side-effects.... antihypertensive drugs

Antiarrhythmic Drugs

ARRHYTHMIA is a variation in the normal rhythm of the heartbeat. Management of the condition requires accurate diagnosis of the type, and ELECTROCARDIOGRAPHY is vital in this process (see HEART, DISEASES OF). Drug treatment is usually part of the management, and antiarrhythmic drugs can be divided clinically into those that act on supraventricular arrhythmias, those that act on both supraventricular and ventricular arrythmias, and those that act on ventricular arrythmias. Respective examples are VERAPAMIL, DISOPYRAMIDE and LIDOCAINE. This large group of drugs can also be classi?ed according to their effects on the electrical reactions of active myocardial cells. The many drugs available are described in the British National Formulary.... antiarrhythmic drugs

Antibacterial Drugs

A group of drugs, which include ANTIBIOTICS, used to treat infections caused by BACTERIA. Drugs include CEPHALOSPORINS and cephamycins, TETRACYCLINES, AMINOGLYCOSIDES, MACROLIDES, and antituberculous compounds.... antibacterial drugs

Antihistamine Drugs

Antihistamine drugs antagonise the action of HISTAMINE and are therefore of value in the treatment of certain allergic conditions (see ALLERGY). They may be divided into those with a central action (e.g. ?upheniramine and cyclizine) and those such as loratidine and terfenadine with almost no central action. Antihistamines are also of some value in the treatment of vasomotor RHINITIS (see also under NOSE, DISORDERS OF); they reduce rhinorrhoea and sneezing but are usually less e?ective in relieving nasal congestion. All antihistamines are useful in the treatment of URTICARIA and certain allergic skin rashes, insect bites and stings, as well as in the treatment of drug allergies. Chlorpheniramine or promethazine injections are useful in the emergency treatment of angio-oedema (see under URTICARIA) and ANAPHYLAXIS.

There is little evidence that any one antihistamine is superior to another, and patients vary considerably in their response to them. The antihistamines di?er in their duration of action and in the incidence of side-effects such as drowsiness. Most are short-acting, but some (such as promethazine) work for up to 12 hours. They all cause sedation but promethazine, trimeprazine and dimenhydrinate tend to be more sedating while chlorpheniramine and cyclizine are less so, as are astemizole, oxatomide and terfenadine. Patients should be warned that their ability to drive or operate machinery may be impaired when taking these drugs, and that the effects of ALCOHOL may be increased.... antihistamine drugs

Antipsychotic Drugs

See NEUROLEPTICS.... antipsychotic drugs

Cytotoxic Drugs

Chemicals used to kill cancerous cells. Most cytotoxic drugs also kill normal cells. There is a delicate balance between killing enough cancer cells and not so many normal cells.... cytotoxic drugs

Dangerous Drugs

See CONTROLLED DRUGS.... dangerous drugs

Designer Drugs

A group of chemical substances produced illegally whose properties and effects are similar to those of drugs of abuse. They may be derived from narcotic ANALGESICS, AMPHETAMINES or HALLUCINOGENS. Ecstasy is a widely used designer drug and has caused deaths among teenagers. Designer drugs are potentially dangerous, especially if taken with alcohol.... designer drugs

Antidepressant Drugs

These widely used drugs include a range of different preparations which relieve DEPRESSION. All the antidepressants available at the time of writing are more or less equally e?ective. In studies where patients agree to take either antidepressants or identical dummy PLACEBO pills (without knowing which), at least two-thirds of those who receive antidepressants feel much better within three months, while fewer than one-third of those on placebos recover naturally in the same period. In general these drugs are useful for severe and moderate depression including postnatal illness; they are not e?ective in milder forms of depression although they may be tried for a short time if other therapies have failed.

The most widely prescribed type of antidepressants are the tricyclics, so-called because their molecular structure includes three rings. The other commonly used types are named after the actions they have on chemicals in the brain: the SELECTIVE SEROTONIN-REUPTAKE INHIBITORS (SSRIS) and the MONOAMINE OXIDASE INHIBITORS (MAOIS) – see also below. All types of antidepressant work in similar ways. Tricyclic antidepressants have cured depression in millions of people, but they can cause unpleasant side-effects, particularly in the ?rst couple of weeks. These include SEDATION, dry mouth, excessive sweating, CONSTIPATION, urinary problems, and impotence (inability to get an erection). Up to half of all people prescribed tricyclic drugs cannot tolerate the side-effects and stop treatment before their depression is properly treated. More seriously, tricyclics can upset the rhythm of the heart in susceptible people and should never be given in the presence of heart disease.

The SSRIs are newer, coming into wide use in the late 1980s. They increase the levels in the brain of the chemical messenger SEROTONIN, which is thought to be depleted in depression. Indeed, the SSRIs are as e?ective as tricyclics and, although they can cause nausea and excessive sweating at ?rst, they generally have fewer side-effects. Their main disadvantage, however, is that they cost much more than the most commonly used tricyclic, amitriptyline. On the other hand, they are more acceptable to many patients and they cause fewer drop-outs from treatment – up to a quarter rather than a half. The money saved by completed, successful treatment may outweigh the prescribing costs. SSRIs have been reported as associated with an increased risk of suicide.

Another group of antidepressants, the MAOIs, have been in use since the late 1950s.

They are stimulants, rather than sedatives, and are particularly helpful for people who are physically and mentally slowed by depression. They work well but have one big disadvantage – a dangerous interaction with certain foods and other drugs, causing a sudden and very dangerous increase in blood pressure. People taking them must carry an information card explaining the risk and listing the things that they should avoid. Because of this risk, MAOIs are not used much now, except when other treatments have failed. A new MAOI, moclobemide, which is less likely to interact and so cause high blood pressure, is now available.

LITHIUM CARBONATE is a powerful antidepressant used for intractable depression. It should be used under specialist supervision as the gap between an e?ective dose and a toxic one is narrow.

St John’s Wort is a popular herbal remedy which may be e?ective, but which is handicapped by di?erences of strength between di?erent preparations or batches. It can interact with a number of conventional drugs and so needs to be used cautiously and with advice.

In general, antidepressants work by restoring the balance of chemicals in the brain. Improved sleep and reduced anxiety are usually the ?rst signs of improvement, particularly among people taking the more sedative tricyclic drugs. Improvement in other symptoms follow, with the mood starting to lift after about two weeks of treatment. Most people feel well by three months, although a few residual symptoms, such as slowness in the mornings, may take longer to clear up. People taking antidepressants usually want to stop them as soon as they feel better; however, the risk of relapse is high for up to a year and most doctors recommend continuing the drugs for around 4–6 months after recovery, with gradual reduction of the dose after that.

Withdrawal reactions may occur including nausea, vomiting, headache, giddiness, panic or anxiety and restlessness. The drugs should be withdrawn gradually over about a month or longer (up to six months in those who have been on maintenance treatment).

A wide range of antidepressant drugs is described in the British National Formulary. Examples include:

Tricyclics: amitryptyline, imipramine, doxepin.

MAOIs: phenelzine, isocarboxazid.

SSRIs: citalopram, ?uoxetine, paraxtene. (Antidepressant drugs not in these three

groups include ?upenthixol, mertazapine and venlafaxine.)... antidepressant drugs

Fibrinolytic Drugs

A group of drugs, also known as thrombolytics, with the ability to break down the protein FIBRIN, the prime constituent of blood clots (see THROMBUS; THROMBOSIS). They are used to disperse blood clots that have formed in the vessels of the circulatory system. The group includes STREPTOKINASE, alteplase and reteplase. The drugs work by activating PLASMINOGEN to form PLASMIN which degrades ?brin and breaks up the blood clot (see COAGULATION).... fibrinolytic drugs

Ulcer Healing Drugs

A variety of drugs with di?ering actions are available for the treatment of peptic ulcer, the composite title covering gastric ulcer (see STOMACH, DISEASES OF) and DUODENAL ULCER. Peptic ulceration may also involve the lower OESOPHAGUS, and after stomach surgery the junction of the stomach and small intestine.

The drugs used in combination are:

The receptor antagonists, which reduce the output of gastric acid by histamine H2receptor blockade; they include CIMETIDINE, FAMOTIDINE and RANITIDINE.

ANTIBIOTICS to eradicate Helicobacter pylori infection, a major cause of peptic ulceration. They are usually used in combination with one of the PROTON-PUMP INHIBITORS and include clarithomycin, amoxacillin and metronidazole.

BISMUTH chelates.

The prostaglandin analogue misoprostol has antisecretory and protective properties.

Proton-pump inhibitors omeprazole, lansoprazole, pantaprazole and rabeprazole, all of which inhibit gastric-acid secretion by blocking the proton pump enzyme system.... ulcer healing drugs

Antidiabetic Drugs

A group of drugs used to treat diabetes mellitus, in which a lack of insulin, or resistance to its actions, results in raised blood glucose levels. A wide range of antidiabetics are used to keep the blood glucose level as close to normal as possible, and consequently reduce the risk of complications such as vascular (blood vessel) disease.

Antidiabetic drugs include insulin, which must be administered by injection, and oral hypoglycaemics such as glibenclamide and metformin. Acarbose and guar gum reduce or slow absorption of carbohydrate from the intestines after meals. Repaglinide stimulates insulin release from the pancreas for a short time and may be taken directly before meals. Rosiglitazone reduces resistance to the effects of insulin in the tissues and may be used together with other hypoglycaemics.... antidiabetic drugs

Antithyroid Drugs

Drugs used to treat hyperthyroidism, in which the thyroid gland is overactive. They may be used as the sole treatment or before thyroid surgery. Carbimazole and propylthiouracil interfere with the production of thyroid hormone by the gland.... antithyroid drugs

Adverse Reactions To Drugs

When a new drug is introduced, it has usually been studied only in relatively few patients – typically 1,500. If n patients have been studied, and no serious effects observed, there is still a chance of a serious adverse e?ect occurring in the general population as frequently as 3/n (1:500).

Adverse effects can be divided into types. First, those which are closely related to the concentration of the drug and accord with what is known of its PHARMACOLOGY. These so-called type A (augmented pharmacological) effects are distinguished from type B (bizarre) effects which are unpredictable, usually rare, and often severe. ANAPHYLAXIS is the most obvious of these; other examples include bone-marrow suppression with CO-TRIMOXAZOLE; hepatic failure (see HEPATITIS) with SODIUM VALPROATE; and PULMONARY FIBROSIS with AMIODARONE. A more comprehensive classi?cation includes reactions type C (chronic effects), D (delayed effects – such as teratogenesis or carcinogenesis) and E (end-of-dose effects – withdrawal effects). Examples of adverse reactions include nausea, skin eruptions, jaundice, sleepiness and headaches.

While most reported adverse reactions are minor and require no treatment, patients should remind their doctors of any drug allergy or adverse e?ect they have suffered in the past. Medical warning bracelets are easily obtained. Doctors should report adverse effects to the authorities – in the case of Britain, to the Committee on Safety of Medicines (CSM), using the yellow-card reporting machinery.... adverse reactions to drugs

Anti-inflammatory Drugs

See ANALGESICS; NON-STEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDS).... anti-inflammatory drugs

Essential Drugs

Any of the therapeutic substances considered indispensable for the rational care of the vast majority of diseases in a given population.... essential drugs

Lipid-regulating Drugs

These drugs reduce the amount of low-density LIPOPROTEINS, which transport CHOLESTEROL and triglycerides (see TRIGLYCERIDE) in the blood, or raise the concentration of high-density lipoproteins. The aim is to reduce the progression of ATHEROSCLEROSIS and therefore help prevent coronary heart disease (see HEART, DISEASES OF). These drugs should be combined with reducing other risk factors for raised lipid concentrations, such as a high-fat diet, smoking and obesity. Lipid-regulating drugs include STATINS, ?brates, anion-exchange resins, and NICOTINIC ACID, which may be used singly or in combination under careful medical supervision (see HYPERLIPIDAEMIA).... lipid-regulating drugs

Prescription Drugs

All those medications requiring written notification from a doctor to a pharmacist before they can be dispensed.... prescription drugs

Psychedelic Drugs

Drugs, such as CANNABIS and LYSERGIC ACID DIETHYLAMIDE (LSD), that expand consciousness and perception. (See DEPENDENCE.)... psychedelic drugs

Thiazolidinedione Drugs

A group of drugs used to treat type-2 diabetes (see under DIABETES MELLITUS) which work by suppressing the activity of RESISTIN, a recently discovered hormone that acts against INSULIN. Resistin links obesity to type-2 diabetes which has long been known to be associated with overweight subjects.... thiazolidinedione drugs

Beta-adrenoceptor-blocking Drugs

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

Drugs In Pregnancy

Unnecessary drugs during pregnancy should be avoided because of the adverse e?ect of some drugs on the fetus which have no harmful e?ect on the mother. Drugs may pass through the PLACENTA and damage the fetus because their pharmacological effects are enhanced as the enzyme systems responsible for their degradation are undeveloped in the fetus. Thus, if the drug can pass through the placenta, the pharmacological e?ect on the fetus may be great whilst that on the mother is minimal. WARFARIN may thus induce fetal and placental haemorrhage and the administration of THIAZIDES may produce THROMBOCYTOPENIA in the newborn. Many progestogens have androgenic side-effects and their administration to a mother for the purpose of preventing recurrent abortion may produce VIRILISATION of the female fetus. Tetracycline administered during the last trimester commonly stains the deciduous teeth of the child yellow.

The other dangers of administering drugs in pregnancy are the teratogenic effects (see TERATOGENESIS). It is understandable that a drug may interfere with a mechanism essential for growth and result in arrested or distorted development of the fetus and yet cause no disturbance in the adult, in whom these di?erentiation and organisation processes have ceased to be relevant. Thus the e?ect of a drug upon a fetus may di?er qualitatively as well as quantitatively from its e?ect on the mother. The susceptibility of the embryo will depend on the stage of development it has reached when the drug is given. The stage of early di?erentiation – that is, from the beginning of the third week to the end of the tenth week of pregnancy – is the time of greatest susceptibility. After this time the risk of congenital malformation from drug treatment is less, although the death of the fetus can occur at any time.... drugs in pregnancy

Ace Inhibitor Drugs

A group of vasodilator drugs used to treat heart failure, hypertension, and diabetic nephropathy. (angiotensin converting enzyme) inhibitors are often prescribed with other drugs such as diuretic drugs or betablocker drugs. Possible side effects include nausea, loss of taste, headache, dizziness, and dry cough.... ace inhibitor drugs

Alpha-blocker Drugs

A group of drugs used to treat hypertension (high blood pressure) and urinary symptoms due to enlargement of the prostate gland. Alpha-blockers are also used to treat urinary retention caused by an enlarged prostate gland (see prostate, enlarged). Side effects of the drugs may include dizziness and fatigue due to a sudden drop in blood pressure, nausea, dry mouth, and drowsiness.... alpha-blocker drugs

Controlled Drugs

In the United Kingdom, controlled drugs are those preparations referred to under the Misuse of Drugs Act 1971. The Act prohibits activities related to the manufacture, supply and possession of these drugs, and they are classi?ed into three groups which determine the penalties for o?ences involving their misuse. For example, class A includes COCAINE, DIAMORPHINE, MORPHINE, LSD (see LYSERGIC ACID DIETHYLAMIDE and PETHIDINE HYDROCHLORIDE. Class B includes AMPHETAMINES, BARBITURATES and CODEINE. Class C includes drugs related to amphetamines such as diethylpropion and chlorphentermine, meprobamate and most BENZODIAZEPINES and CANNABIS.

The Misuse of Drugs Regulations 1985 de?ne the classes of person authorised to supply and possess controlled drugs, and lay down the conditions under which these activities may be carried out. In the Regulations, drugs are divided into ?ve schedules specifying the requirements for supply, possession, prescribing and record-keeping. Schedule I contains drugs which are not used as medicines. Schedules II and III contain drugs which are subject to the prescription requirements of the Act (see below). They are distinguished in the British National Formulary (BNF) by the symbol CD and they include morphine, diamorphine (heroin), other opioid analgesics, barbiturates, amphetamines, cocaine and diethylpropion. Schedules IV and V contain drugs such as the benzodiazepines which are subject to minimal control. A full list of the drugs in each schedule can be found in the BNF.

Prescriptions for drugs in schedules II and III must be signed and dated by the prescriber, who must give his or her address. The prescription must be in the prescriber’s own handwriting and provide the name and address of the patient and the total quantity of the preparation in both words and ?gures. The pharmacist is not allowed to dispense a controlled drug unless all the information required by law is given on the prescription.

Until 1997 the Misuse of Drugs (Noti?cation and Supply of Addicts) Regulations 1973 governed the noti?cation of addicts. This was required in respect of the following commonly used drugs: cocaine, dextromoramide, diamorphine, dipipanone, hydrocodeine, hydromorphone, levorphanol, methadone, morphine, opium, oxycodone, pethidine, phenazocine and piritranide.

In 1997 the Misuse of Drugs (Supply to Addicts) Regulations 1997 revoked the 1973 requirement for noti?cation. Doctors are now expected to report (on a standard form) cases of drug misuse to their local Drug Misuse Database (DMD). Noti?cation by the doctor should be made when a patient ?rst presents with a drug problem or when he or she visits again after a gap of six months or more. All types of misuse should be reported: this includes opioids, benzodiazepines and central nervous system stimulants. The data in the DMD are anonymised, which means that doctors cannot check on possible multiple prescribing for drug addicts.

The 1997 Regulations restrict the prescribing of diamorphine (heroin), Diconal® (a morphine-based drug) or cocaine to medical practitioners holding a special licence issued by the Home Secretary.

Fuller details about the prescription of controlled drugs are in the British National Formulary, updated twice a year, and available on the Internet (see www.bnf.org).... controlled drugs

Misuse Of Drugs

See also MEDICINES. Government legislation covers the manufacture, sale and prescription of drugs in the UK. As well as stating which drugs may be sold over the counter (OTC) without a doctor’s or dentist’s prescription, and those which can be obtained only with such a prescription, government regulations determine the extent of availability of many substances which are liable to be abused – see Misuse of Drugs Act 1971 (below). The Misuse of Drugs Regulations 1985 de?ne those individuals who in their professional capacity are authorised to supply and possess controlled drugs: see the schedules of drugs listed below under the 1985 regulations.

Misuse of Drugs Act 1971 This legislation forbids activities relating to the manufacture, sale and possession of particular (controlled) drugs. These are classi?ed into three grades according to their dangers if misused. Any o?ences concerning class A drugs, potentially the most damaging when abused, carry the toughest penalties, while classes B and C attract lesser penalties if abused.

Class A includes: cocaine, dextromoramide, diamorphine (heroin), lysergic acid (LSD), methadone, morphine, opium, pethidine, phencyclidine acid and injectable preparations of class B drugs.

Class B includes: oral amphetamines, barbiturates, codeine, glutethimide, marijuana (cannabis), pentazocine and pholcodine.

Class C includes: drugs related to the amphetamines, anabolic and androgenic steroids, many benzodiazepines, buprenorphine, diethyl propion, human chorionic gonadotrophin (HCG), mazindol, meprobamate, pemoline, phenbuterol, and somatropin.

Misuse of Drugs Regulations 1985 These regulations de?ne those people who are authorised in their professional capacity to supply and possess controlled drugs. They also describe the requirements for legally undertaking these activities, such as storage of the drugs and limits on their prescription.

Drugs are divided into ?ve schedules and some examples follow.

I: Almost all are prohibited except in accordance with Home O?ce authority: marijuana (cannabis), LSD.

II: High potential for abuse but have

accepted medical uses: amphetamines, cocaine.

III: Lower potential for abuse: barbiturates, meprobamate, temazepam.

IV: Lower potential for abuse than I to III. Minimal control: benzodiazepines.

V: Low potential for abuse: generally compound preparations containing small amounts of opioids: kaolin and morphine (antidiarrhoeal medicine), codeine linctus (cough suppressant).

(See also CONTROLLED DRUGS.)... misuse of drugs

Amfetamine Drugs

A group of stimulant drugs used mainly in the treatment of narcolepsy (a rare disorder characterized by excessive sleepiness).

In high doses, amfetamines can cause tremor, sweating, anxiety, and sleeping problems. Delusions, hallucinations, high blood pressure, and seizures may also occur. Prolonged use may produce tolerance and drug dependence.

Amfetamines are often abused for their stimulant effect.... amfetamine drugs

Aminoglycoside Drugs

A type of antibiotic drug. Aminoglycoside drugs are given by injection and are generally reserved for the treatment of serious infections because their use can damage the inner ear or kidneys. Important examples are gentamicin and streptomycin, which are also used topically for eye and ear infections.... aminoglycoside drugs

Amphetamine Drugs

See amfetamine drugs.... amphetamine drugs

Analeptic Drugs

Drugs that stimulate breathing. Replaced by ventilation, they are seldom used now.... analeptic drugs

Non-steroidal Anti-inflammatory Drugs (nsaids)

These act by inhibiting the formation of PROSTAGLANDINS which are mediators of INFLAMMATION. They act both as ANALGESICS to relieve pain, and as inhibitors of in?ammation. Aspirin is a classic example of such a compound. Newer compounds have been synthesised with the aim of producing fewer and less severe side-effects. They are sometimes preferred to aspirin for the treatment of conditions such as RHEUMATOID ARTHRITIS, OSTEOARTHRITIS, sprains, strains and sports injuries. Their main side-effects are gastrointestinal: gastric ulcers and gastric haemorrhage may result (see STOMACH, DISEASES OF). This is because prostaglandins are necessary for the production of the mucous protective coat in the stomach and, when the production of prostaglandin is inhibited, the protection of the stomach is compromised. NSAIDs should therefore be used with caution in patients with DYSPEPSIA and gastric ulceration. The various nonsteroidal anti-in?ammatory drugs di?er little from each other in e?cacy, although there is considerable variation in patient response. Ibuprofen is one of the ?rst choices in this group of drugs as it combines good e?cacy with a low incidence of side-effects and administration is only required twice daily. Other drugs in this series include diclofenac, fenbufen, fenclofenac, fenoprofen, feprazone, ?urbiprofen, indomethacin, indoprofen, ketoprofen, ketorolac, naproxen, piroxicam, sulindac, tiaprofenic acid and tolmetin.... non-steroidal anti-inflammatory drugs (nsaids)

Safety Of Drugs

The COMMITTEE ON SAFETY OF MEDICINES (CSM) has the function of scrutinising the e?cacy, quality and safety of new DRUGS before clinical trials and before marketing, as well as the surveillance of each drug after marketing so that adverse reactions are monitored and documented, and warnings issued as required. Early clinical trials of a drug can only be carried out after a clinical-trial certi?cate has been issued by the licensing authority.

The major defect in this system is the dif?culty in obtaining reports of adverse reactions. Evidence suggests that at most, about 10 per cent of such reactions are reported. One method of trying to obtain this information is the ‘yellow card’ system. It is so called because it is based on the distribution of yellow cards to all doctors, pharmacists and dentists, on which they are asked to report any adverse reaction happening to someone taking a drug, whether or not they think it is the cause. Alternatively the CSM has a Freephone line and on-line computer facilities (ADROIT) for practitioners to use. Even though the annual number of adverse reactions reported in this way has risen from around 5,000 in 1975 to more than 18,000, this is probably fewer than the number actually occurring.

Two further committees in this safety screen are the Joint Committee on Vaccination and Immunisation and the Adverse Reactions to Vaccines and Immunological Substances Committee.... safety of drugs

Sympathomimetic Drugs

These drugs stimulate the activity of the SYMPATHETIC NERVOUS SYSTEM. There are three groups: inotropic and vasoconstrictor sympathomimetics, and those used for cardiopulmonary resuscitation. The properties of these drugs vary according to whether they act on alpha or beta adrenergic receptors.

Inotropics act on beta receptors in heart muscle (see HEART), increasing its contractility and sometimes the heart rate. DOBUTAMINE and DOPAMINE are cardiac stimulants, while dopexamine acts on heart muscle and, via peripheral dopamine receptors, increases the excretion of URINE. ISOPRENALINE is used only as emergency treatment of heart block (interruption of the heart’s conduction) or severe slowing of the heart rate (bradycardia).... sympathomimetic drugs

Tricyclic Antidepressant Drugs

This group of drugs is one of three main types of drugs used to treat DEPRESSION, and was the ?rst to be introduced (in the 1950s). Tricyclic drugs work by blocking the re-uptake of the neurotransmitters SEROTONIN and NORADRENALINE (see NEUROTRANSMITTER), thus increasing the amount of the neurotransmitters at the nerve cell’s receptors. In people with depression, fewer neurotransmitters than normal are released, resulting in a slowing of neural activities. The drugs have a sedative e?ect, which can be useful for depressives with sleep problems, and an antimuscarinic action which can cause dry mouth and constipation (see ANTIMUSCARINE). Overdosage can produce COMA, ?ts (see SEIZURE) and irregular heart rhythm (ARRHYTHMIA). They are sometimes used for treating bed-wetting. (See also ANTIDEPRESSANT DRUGS.)... tricyclic antidepressant drugs

Antacid Drugs

Drugs taken to relieve the symptoms of indigestion, heartburn, oesophagitis, acid reflux, and peptic ulcer. Antacids usually contain compounds of magnesium or aluminium, which neutralize stomach acid. Some also contain alginates, which protect the lining of the oesophagus from stomach acid, or dimeticone, an antifoaming agent, which helps to relieve flatulence.

Aluminium may cause constipation and magnesium may cause diarrhoea; but these effects may be avoided if a preparation contains both ingredients.

Antacids interfere with the absorption of many drugs and should not be taken at the same time as other drugs.... antacid drugs

Anthelmintic Drugs

A group of drugs that are used to eradicate worm infestations. Possible side effects include nausea, abdominal pain, rash, headache, and dizziness.... anthelmintic drugs

Antiallergy Drugs

Drugs that are used to treat or prevent allergic reactions (see allergy). There are several groups, including corticosteroids, antihistamines, leukotriene receptor antagonists, and sodium cromoglicate.... antiallergy drugs

Antianxiety Drugs

A group of drugs used to relieve the symptoms of anxiety. Benzodiazepine drugs and beta-blocker drugs are the 2 main types, although antidepressant drugs may occasionally be used. Benzodiazepine drugs promote mental and physical relaxation; they can also be used to treat insomnia, but their use for this purpose is avoided because they are addictive. Beta-blockers reduce only the physical symptoms of anxiety, such as shaking and palpitations, and are not addictive.... antianxiety drugs

Anticoagulant Drugs

A group of drugs used to treat and prevent abnormal blood clotting, to treat thrombosis, and to prevent and treat stroke and transient ischaemic attack. Anticoagulant drugs are also given to prevent abnormal blood clotting after major surgery (especially heart-valve replacement) or during haemodialysis (see dialysis). The most common anticoagulants are heparin and the newer heparin-derived drugs, such as tinzaparin, all of which have to be given by injection, and warfarin, which is taken orally.

Excessive doses of anticoagulant drugs increase the risk of unwanted bleeding, and regular monitoring is needed.... anticoagulant drugs

Analgesic Drugs

Drugs used to relieve pain. The 2 main types are nonopioid and opioid. Nonopioid analgesics, which include aspirin, paracetamol, and nonsteroidal anti-inflammatory drugs (NSAIDs), are useful in the treatment of mild to moderate pain (for example, headache or toothache). Combinationsof a weak opioid analgesic, such as codeine, with a nonopioid analgesic relieve more severe pain. Potent opioids such as morphine are used only when other preparations would be ineffective because they can produce tolerance and drug dependence.

Adverse effects are uncommon with paracetamol. Aspirin and NSAIDs may irritate the stomach lining and cause nausea, abdominal pain, and, rarely, a peptic ulcer. Nausea, drowsiness, constipation, and breathing difficulties may occur with opioid analgesics.... analgesic drugs

Androgen Drugs

Natural or synthetic androgen hormones used as drugs; one of the most important is testosterone. These drugs are used in the treatment of male hypogonadism (underactivity of the testes) to stimulate the development of sexual characteristics.

Androgen drugs are occasionally used to treat certain types of breast cancer. They have been widely used by sportsmen wishing to increase muscle bulk and strength, a practice that is dangerous to health (see steroids, anabolic).

Adverse effects include fluid retention, weight gain, increased blood cholesterol, and, rarely, liver damage. When taken by women, the drugs can cause male characteristics, such as facial hair, to develop.

androgen hormones A group of hormones that stimulate the development of male sexual characteristics.

Androgens are produced by specialized cells in the testes in males and in the adrenal glands in both sexes. The ovaries secrete very small quantities of androgens until the menopause. The most active androgen is testosterone, which is produced in the testes. The production of androgens by the testes is controlled by certain pituitary hormones, called gonadotrophins. Adrenal androgens are controlled by ACTH, another pituitary hormone.

Androgens stimulate male secondary sexual characteristics at puberty, such as the growth of facial hair and deepening of the voice. They have an anabolic effect (they raise the rate of protein synthesis and lower the rate at which it is broken down). This increases muscle bulk and accelerates growth. At the end of puberty, androgens cause the long bones to stop growing. They stimulate sebum secretion, which, if excessive, causes acne. In early adult life, androgens promote male-pattern baldness.

Androgen deficiency may occur if the testes are diseased or if the pituitary gland fails to secrete gonadotrophins. Typical effects include decreased body and facial hair, a high-pitched voice, underdevelopment of the genitalia, and poor muscle development.

Overproduction of androgens may be the result of adrenal disorders (see adrenal tumours; adrenal hyperplasia, congenital), of testicular tumours (see testis, cancer of), or, rarely, of androgensecreting ovarian tumours (see ovary, cancer of).

In men, excess androgens accentuate male characteristics; in boys, they cause premature sexual development.

In women, excess androgens cause virilization, the development of masculine features such as an increase in body hair, deepening of the voice, clitoral enlargement, and amenorrhoea.... androgen drugs

Antibiotic Drugs

A group of drugs used to treat infections caused by bacteria and to prevent bacterial infection in cases of immune system impairment.

Most of the commonly used antibiotic drugs belong to one of the following classes: penicillins, quinolones, aminoglycosides, cephalosporins, macrolides, and tetracyclines. Some antibiotics are effective against only certain types of bacteria; others, which are known as broad-spectrum antibiotics, are effective against a wide range.

Some bacteria develop resistance to a previously effective antibiotic drug. This is most likely to occur during long-term treatment. Some alternative antibiotics are available to treat bacteria that have become resistant to the more commonly prescribed drugs.

Most antibiotic drugs can cause nausea, diarrhoea, or a rash. Antibiotics may disturb the normal balance between certain types of bacteria and fungi in the body, leading to proliferation of the fungi that cause candidiasis (thrush). Some people experience a severe allergic reaction to the drugs, resulting in facial swelling, itching, or breathing difficulty.... antibiotic drugs

Anticonvulsant Drugs

A group of drugs used to treat or prevent seizures. They are used mainly in the treatment of epilepsy but are also given to prevent seizures following serious head injury or some types of brain surgery. They may be needed to control seizures in children with a high fever (see convulsions, febrile).

Anticonvulsants may produce various side effects, including impaired memory, reduced concentration, poor coordination, and fatigue. If the side effects are severe, they can often be minimized by use of an alternative anticonvulsant.... anticonvulsant drugs

Antidiarrhoeal Drugs

Drugs used to reduce or stop diarrhoea and to help regulate bowel action in people with a colostomy or ileostomy.

In most acute cases of diarrhoea, the only treatment recommended is oral rehydration therapy.

Antidiarrhoeal drugs include adsorbents, bulk-forming agents such as kaolin, and antimotility drugs (including the opioid drugs, morphine and codeine, and loperamide), which slow movement through the intestine.

None of these drugs are suitable for children.... antidiarrhoeal drugs

Antiemetic Drugs

A group of drugs used to treat nausea and vomiting.

Antihistamine drugs and anticholinergic drugs reduce vomiting in motion sickness, vertigo, and Ménière’s disease.

The most powerful antiemetics are used to control nausea and vomiting associated with radiotherapy or anticancer drugs.

These drugs include serotonin antagonists such as ondansetron and nabilone.

Antiemetics are not normally used in the treatment of food poisoning because the body needs to rid itself of harmful substances.

Only certain antiemetics can be used to treat vomiting in early pregnancy because damage to the developing fetus may occur.

Many antiemetics cause drowsiness.... antiemetic drugs

Anticancer Drugs

Drugs that are used to treat many forms of cancer. They are particularly useful in the treatment of lymphomas, leukaemias, breast cancer, cancer of the testis (see testis, cancer of), and prostate cancer and are often used together with surgery or radiotherapy.

Most anticancer drugs are cytotoxic (kill or damage rapidly dividing cells), but some act by slowing the growth of hormone-sensitive tumours. Anticancer drugs are often prescribed in combination to maximize their effects.

Treatment with cytotoxic drugs is often given by injection in short courses repeated at intervals. Some drugs cause nausea and vomiting and may result in hair loss and increased susceptibility to infection. Others, such as tamoxifen, which is used for breast cancer, are given continuously by mouth for months or years and cause few side effects.... anticancer drugs

Anticholinergic Drugs

A group of drugs that block the effects of acetylcholine, a chemical released from nerve endings in the parasympathetic autonomic nervous system. Acetylcholine stimulates muscle contraction, increases secretions in the mouth and lungs, and slows the heartbeat.

Anticholinergic drugs are used in the treatment of irritable bowel syndrome, urinary incontinence, Parkinson’s disease, asthma, and bradycardia (abnormally slow heartbeat).

They are also used to dilate the pupil before eye examination or surgery.

Anticholinergic drugs are used as a premedication before general anaesthesia and to treat motion sickness.

They may cause dry mouth, blurred vision, urinary retention, and confusion.... anticholinergic drugs

Antifungal Drugs

A group of drugs used to treat infections caused by fungi. Antifungal drugs are commonly used to treat different types of tinea, including athlete’s foot and scalp ringworm. They are also used for candidiasis (thrush) and rare fungal infections, such as cryptococcosis, that affect internal organs.

Antifungal preparations are available in various forms including tablets, injection, creams, and pessaries. Prolonged treatment of serious fungal infections can result in side effects that include liver or kidney damage.... antifungal drugs

Anti-inflammatory Drugs

Drugs that reduce inflammation. The main groups of these drugs are nonsteroidal antiinflammatory drugs and corticosteroid drugs. (See also analgesic drugs.)... anti-inflammatory drugs

Antimalarial Drugs

Drugs used to treat malaria. One antimalarial drug, chloroquine, is also used to treat arthritis.... antimalarial drugs

Antiplatelet Drugs

Drugs that reduce the tendency of platelets to stick together to form blood clots when blood flow in the arteries is disrupted. This action reduces the risk of thromboembolism, which can cause potentially fatal disorders such as a myocardial infarction or stroke. Aspirin and dipyridamole are commonly used antiplatelet drugs. Others, such as ticlopidine, are used specifically to protect against clots forming in the coronary arteries of people with angina.... antiplatelet drugs

Antipruritic Drugs

Drugs that are used to relieve persistent itching (pruritus).

Antipruritics may be applied as creams and emollients and may contain corticosteroid drugs, antihistamine drugs, or local anaesthetics.

Oral antihistamines may also be used to relieve itching.... antipruritic drugs

Antipyretic Drugs

Drugs that reduce fever. Examples of antipyretic drugs include paracetamol, aspirin, and other non-steroidal anti-inflammatory drugs.... antipyretic drugs

Antiretroviral Drugs

Drugs that are used to slow or halt the spread of viruses in people with HIV infection and AIDS. There are 3 main groups: reverse transcriptase inhibitors, protease inhibitors, and non-nucleoside reverse transcriptase inhibitors. Drugs from different groups are often used in combination. Antiretroviral drugs can have a range of side effects, including nausea, vomiting, diarrhoea, tiredness, and a range of effects on blood chemistry, particularly involving fats.... antiretroviral drugs

Antirheumatic Drugs

A group of drugs used to treat rheumatoid arthritis and types of arthritis that are caused by other autoimmune disorders such as systemic lupus erythematosus.

Antirheumatic drugs affect the disease process and may limit joint damage, unlike nonsteroidal anti-inflammatory drugs, which only relieve pain and stiffness.

The main antirheumatic drugs are corticosteroid drugs, immunosuppressant drugs, chloroquine, gold, penicillamine, and sulfasalazine.

Many of these drugs can have serious side effects, and treatment must be under specialist supervision.... antirheumatic drugs

Antispasmodic Drugs

A group of drugs that relax spasm in smooth muscle in the wall of the intestine or bladder. These drugs are used to treat irritable bowel syndrome and irritable bladder. Possible side effects include dry mouth, blurred vision, and difficulty in passing urine. (See also anticholinergic drugs.)... antispasmodic drugs

Antitussive Drugs

Drugs that suppress or relieve a cough (see cough remedies).... antitussive drugs

Antiviral Drugs

Drugs used in the treatment of infection by viruses. No drugs have been developed that can eradicate viruses, and at present immunization is the most effective way of preventing serious viral infections.

However, antiviral drugs can reduce the severity of some viral infections (most notably herpes, influenza, viral hepatitis, and cytomegalovirus infections), particularly in people who have reduced immunity.

Advances have also been made in the treatment of infection (see antiretroviral drugs).... antiviral drugs

Barbiturate Drugs

A group of sedative drugs that work by depressing activity within the brain. They include thiopental and phenobarbital. In the past, barbiturates were widely used as antianxiety drugs and sleeping drugs but have been largely replaced by benzodiazepine drugs and other nonbarbiturates. Barbiturates are now strictly controlled because they are habit-forming and widely abused. An overdose can be fatal, particularly in combination with alcohol, which dangerously increases the depressant effect on the brain (including suppression of the respiratory centre). However, phenobarbital is still commonly used as an anticonvulsant drug in the treatment of epilepsy. Thiopental is very short acting and is used to induce anaesthesia (see anaesthesia, general).... barbiturate drugs

Benzodiazepine Drugs

A group of drugs given for short periods as sleeping drugs for insomnia and to control the symptoms of anxiety or stress (see tranquillizer drugs). Common benzodiazepines include diazepam, which is used as a tranquillizer, and nitrazepam, which is sometimes used for insomnia. Benzodiazepines are also used in the management of alcohol withdrawal and in the control of epilepsy.

Minor adverse effects of benzodiazepines include daytime drowsiness, dizziness, and forgetfulness. Unsteadiness and slowed reactions may also occur. Regular users may become psychologically and physically dependent; for this reason, the drugs are usually given for courses of 2–3 weeks or less. When the drugs are stopped suddenly, withdrawal symptoms, such as anxiety, restlessness, and nightmares may occur. Benzodiazepine drugs are sometimes abused for their sedative effect.... benzodiazepine drugs

Beta-blocker Drugs

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

Biphosphonate Drugs

See bisphosphonate drugs.... biphosphonate drugs

Bisphosphonate Drugs

Drugs used to slow bone metabolism (for example in Paget’s disease) and to reduce the high calcium levels in the blood associated with destruction of bone by secondary cancer growths.

Bisphosphonates are also used in the prevention or treatment of osteoporosis.... bisphosphonate drugs

Cephalosporin Drugs

A large group of antibiotic drugs derived from the fungus

CEPHALOSPORIUM ACREMONIUM, which are effective against a wide range of infections.

Cephalosporins are used to treat ear, throat, and respiratory tract infections, and conditions, such as urinary tract infections and gonorrhoea, in which the causative bacteria are resistant to other types of antibiotics.

Occasionally, the drugs cause allergic reactions, such as rash, itching, and fever.

Rarely, anaphylactic shock occurs.

Other side effects include diarrhoea and blood disorders.... cephalosporin drugs

Cox-2 Inhibitor Drugs

A group of non-steroidal anti-inflammatory drugs (NSAIDs) that cause less stomach irritation as a side effect than other NSAIDs. Examples of -2 inhibitors include celecoxib and rofecoxib.... cox-2 inhibitor drugs

Digitalis Drugs

A group of drugs that are extracted from plants belonging to the foxglove family.

They are used to treat heart conditions, most commonly atrial fibrillation.

Those most frequently used are digitoxin and digoxin.... digitalis drugs

Fertility Drugs

A group of hormonal or hormone-related drugs used to treat some types of infertility.

In women, fertility drugs may be given when abnormal hormone production by the pituitary gland or ovaries disrupts ovulation or causes mucus around the cervix to become so thick that sperm cannot penetrate it. In men, fertility drugs are less effective, but they may be used when abnormal hormone production by the pituitary gland or testes interferes with sperm production. (See also clomifene; gonadotrophin hormones; testosterone.)... fertility drugs

Haemostatic Drugs

A group of drugs used to treat bleeding disorders and to control bleeding. Haemostatic preparations that help blood clotting are given to people who have deficiencies of natural clotting factors. For example, factor VIII is used to treat haemophilia. Drugs that prevent the breakdown of fibrin in clots, such as tranexamic acid, can also improve haemostasis.... haemostatic drugs

Bronchodilator Drugs

A group of drugs that widen the bronchioles (small airways in the lungs) to increase air flow and improve breathing, especially in the treatment of asthma and chronic obstructive pulmonary disease (see pulmonary disease, chronic obstructive). There are 3 main types of bronchodilator: sympathomimetic drugs (such as salbutamol), anticholinergic drugs, and xanthine drugs (such as aminophylline). Sympathomimetic drugs are used primarily for the rapid relief of breathing difficulty. Anticholinergic and xanthine drugs are more often used for the long-term prevention of attacks of breathing difficulty. Drugs can be given by inhaler, in tablet form, or, in severe cases, by nebulizer or injection.

The main side effects of sympathomimetics are palpitations and trembling.

Anticholinergics may cause dry mouth, blurred vision, and, rarely, difficulty in passing urine.

Xanthines may cause headaches, nausea and palpitations.... bronchodilator drugs

Corticosteroid Drugs

A group of drugs that are similar to the corticosteroid hormones produced by the adrenal glands. Corticosteroids are used as hormone replacement therapy in Addison’s disease and when the adrenal glands or pituitary gland have been destroyed or removed. They are also used to treat inflammatory intestinal disorders such as ulcerative colitis and Crohn’s disease and as an urgent treatment for inflammation in the artery supplying the retina in temporal arteritis. Other uses include treatment of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis, and treatment of asthma, eczema, and allergic rhinitis. Corticosteroid drugs are also used to prevent organ rejection after transplant surgery and in the treatment of some types of cancer, such as a lymphoma or leukaemia. Corticosteroid injections may relieve pain in disorders such as tennis elbow and arthritis.

Side effects are uncommon when corticosteroids are given as a cream or by inhaler, but tablets taken in high doses for long periods may cause oedema, hypertension, diabetes mellitus, peptic ulcer, Cushing’s syndrome, inhibited growth in children, and, in rare cases, cataract or psychosis. High doses also impair the body’s immune system. Long-term treatment suppresses production of corticosteroid hormones by the adrenal glands, and sudden withdrawal may lead to adrenal failure.... corticosteroid drugs

Decongestant Drugs

Drugs that are used to relieve nasal congestion commonly in people with upper respiratory tract infections.

They work by narrowing blood vessels in the membranes lining the nose.

This action reduces swelling, inflammation, and the amount of mucus produced by the lining.

Common drugs include ephedrine, oxymetazoline, and phenylephrine.

Small amounts of these drugs are present in many over-thecounter cold remedies.

Taken by mouth, decongestant drugs may cause tremor and palpitations.

Adverse effects are unlikely with nose drops, but if taken for several days they become ineffective and symptoms may then recur or worsen despite continued treatment.... decongestant drugs

Diuretic Drugs

Drugs that help remove excess water from the body by increasing the amount lost as urine. They are used in the treatment of various disorders, which include severe premenstrual syndrome, hypertension, heart failure, the eye condition glaucoma, nephrotic syndrome, and cirrhosis of the liver.

Types of diuretic drug differ markedly in their speed and mode of action. Thiazide diuretics cause a moderate increase in urine production. Loop diuretics are fast-acting, powerful drugs. They are often used as an emergency treatment for heart failure. Potassium-sparing diuretics are used along with thiazide and loop diuretics, both of which may cause the body to lose too much potassium. Carbonic anhydrase inhibitors block the action of the enzyme carbonic anhydrase, which affects the amount of bicarbonate ions in the blood; these drugs increase urine output moderately but are effective only for short periods of time. Osmotic diuretics are used to maintain urine output following serious injury or major surgery.

Diuretic drugs may cause chemical imbalances in the blood.

Hypokalaemia (low blood levels of potassium) is usually treated with potassium supplements or potassium-sparing diuretic drugs.

A diet rich in potassium may be helpful.

Some diuretics raise the blood level of uric acid, increasing the risk of gout.

Certain diuretics increase the blood glucose level, which can cause or worsen diabetes mellitus.... diuretic drugs

Hypnotic Drugs

Drugs that induce sleep (see sleeping drugs).... hypnotic drugs

Immunostimulant Drugs

A group of drugs that increase the efficiency of the body’s immune system. Immunostimulant drugs include vaccines, interferon and aldesleukin (interleukin-2). Interferon is used to treat persistent viral infections, such as hepatitis C, and some types of multiple sclerosis. Aldesleukin is used in the treatment of some types of cancer.... immunostimulant drugs

Immunosuppressant Drugs

A group of drugs that reduce the activity of the immune system. They include azathioprine, ciclosporin, cyclophosphamide, methotrexate, and prednisolone. Immunosuppressants are given to prevent rejection after transplant surgery and to slow the progress of autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus.

The drugs work by suppressing the production and activity of white blood cells called lymphocytes. Side effects vary, but all the drugs increase the risk of infection and of the development of certain cancers.... immunosuppressant drugs

Keratolytic Drugs

Drugs that loosen and remove the tough outer layer of skin.

Keratolytic drugs, which include urea and salicylic acid preparations, are used to treat skin and scalp disorders, such as warts, acne, dandruff, and psoriasis.... keratolytic drugs

Laxative Drugs

A group of drugs used to treat constipation.

There are various types.

Bulk-forming laxatives increase the volume and softness of faeces and make them easier to pass.

Stimulant laxatives stimulate the intestinal wall to contract and speed up the elimination of faeces.

Lubricant laxatives soften and facilitate the passage of faeces.

Osmotic laxatives increase the water content and volume of the faeces.

If used in excess, laxative drugs may cause diarrhoea, abdominal cramps, and flatulence, and may impair normal bowel function.... laxative drugs

Lipid-lowering Drugs

A group of drugs used to treat hyperlipidaemia.

These drugs help to prevent, or slow the progression of, severe atherosclerosis and coronary artery disease.

The most commonly used types are statins and fibrates.... lipid-lowering drugs

Macrolide Drugs

A class of antibiotic drugs used to treat a wide range of infections including those of the ear, nose, throat, respiratory and gastrointestinal tracts, and skin.

Common macrolides include azithromycin and erythromycin.... macrolide drugs

Miotic Drugs

Drugs used in the treatment of glaucoma to reduce pressure in the eye. Used topically, miotic drugs cause the pupil to contract, which opens up the drainage channels and drains fluid from the front of the eye. Side effects include headache, particularly over the eye, and blurred vision. Common miotics include carbachol and pilocarpine. (See also mydriatic drugs.)... miotic drugs

Mucolytic Drugs

Drugs that make sputum (phlegm) less sticky and easier to cough up. An example is acetylcysteine.... mucolytic drugs

Muscle-relaxant Drugs

A group of drugs used to relieve muscle spasm and spasticity. Muscle-relaxant drugs are used mainly in the treatment of nervoussystem disorders such as multiple sclerosis and painful muscular conditions such as torticollis. They are occasionally used to relieve muscle rigidity caused by injury. Some types are used to cause temporary paralysis during surgery under general anaesthesia.Except for dantrolene, muscle-relaxant drugs partly block nerve signals that stimulate muscle contraction. Dantrolene interferes with the chemical activity in muscle cells needed for contraction.

The drugs may cause muscle weakness and drowsiness. In rare cases, dantrolene causes liver damage.... muscle-relaxant drugs

Mydriatic Drugs

A group of drugs used to treat uveitis and to dilate the pupil during examination of the inside of the eye and for surgery. Mydriatics work by relaxing the circular muscles of the iris, causing the pupil to dilate. Common mydriatic drugs include tropicamide, cyclopentolate, homatropine, and phenylephrine. (See also cycloplegia; miotic drugs.)... mydriatic drugs

Narcotic Drugs

See opioid analgesic drugs.... narcotic drugs

Nitrate Drugs

A group of vasodilator drugs used to treat angina pectoris (chest pain as a result of impaired blood supply) and severe heart failure (reduced pumping efficiency of the heart). Two commonly used nitrate drugs are glyceryl trinitrate and isosorbide.

Possible side effects of nitrate drugs include headache, flushing, and dizziness. Tolerance (the need for greater amounts of a drug for it to have the same effect) may develop when the drug is taken regularly.... nitrate drugs

Nonsteroidal Anti-inflammatory Drugs

A group of drugs, also known as NSAIDs that produce analgesia (pain relief) and reduce inflammation in joints and soft tissues such as muscles and ligaments.

Nonsteroidal anti-inflammatory drugs are widely used to relieve symptoms caused by types of arthritis, such as rheumatoid arthritis, osteoarthritis, and gout. They do not cure or halt the progress of disease. NSAIDs are also used in the treatment of back pain, menstrual pain, headaches, pain after minor surgery, and soft tissue injuries.

The drugs reduce pain and inflammation by blocking the production of prostaglandins (chemicals that cause inflammation and trigger transmission of pain signals to the brain).

NSAIDs may cause a wide range of side effects, the most important of which are nausea, indigestion, bleeding from the stomach, and, sometimes, peptic ulcer.... nonsteroidal anti-inflammatory drugs

Oestrogen Drugs

A group of synthetically produced drugs that are used in oral contraceptives and to supplement or replace the body’s own oestrogen hormones.

Oestrogen drugs are often used together with progestogen drugs.

Oestrogens suppress the production of gonadotrophin hormones, which stimulate cell activity in the ovaries. High doses are used in postcoital contraception to prevent conception (see contraception, emergency). They are also used to treat, or sometimes prevent, menopausal symptoms and disorders. Oestrogens may be used to treat certain forms of infertility, female hypogonadism, abnormal menstrual bleeding, prostatic cancer (see prostate, cancer of), and certain types of breast cancer.

Oestrogens may cause breast tenderness and enlargement, bloating, weight gain, nausea, reduced sex drive, depression, migraine, and bleeding between periods. Side effects often subside after 2 or 3 months. The drugs can increase the risk of abnormal blood clotting and susceptibility to high blood pressure (see hypertension). Oestrogen drugs should not be taken in pregnancy as they may adversely affect the fetus.... oestrogen drugs

Orphan Drugs

Drugs that have been developed to treat rare conditions but are not manufactured generally.... orphan drugs

Penicillin Drugs

A group of antibiotic drugs.

Natural penicillins are derived from the mould PENICILLIUM; others are synthetic preparations.

Penicillins are used to treat many infective conditions, including tonsillitis, bronchitis, bacterial endocarditis, syphilis, and pneumonia.

They are also given to prevent rheumatic fever from recurring.

Common adverse effects of penicillins are an allergic reaction causing a rash, and diarrhoea.... penicillin drugs

Phenothiazine Drugs

A group of drugs used to treat psychotic illnesses (see antipsychotic drugs) and to relieve severe nausea and vomiting (see antiemetic drugs).

The group includes chlorpromazine, fluphenazine, and perphenazine.... phenothiazine drugs

Progestogen Drugs

A group of drugs similar to progesterone hormone. The drugs are used in oral contraceptives, are prescribed to treat menstrual problems (see menstruation, disorders of), and are included in hormone replacement therapy (HRT). Progestogen drugs are also used to treat premenstrual syndrome, endometriosis, and hypogonadism, and are sometimes used as anticancer drugs. Adverse effects include weight gain, oedema, headache, dizziness, rash, irregular periods, breast tenderness, and ovarian cysts.... progestogen drugs

Pregnancy, Drugs In

Certain drugs taken during pregnancy may pass to the fetus through the placenta or interfere with fetal development. This may lead to birth defects. Although relatively few drugs have been proved to cause harm to a developing baby, no drug should be considered completely safe, especially during early pregnancy. For this reason, pregnant women should seek advice from their doctor or pharmacist before taking any drug, including over-thecounter preparations.

Problems may also be caused in a developing baby if a pregnant woman drinks alcohol, smokes (see tobaccosmoking), or takes drugs of abuse. The babies of women who use heroin during pregnancy tend to have a low birthweight and a higher death rate than normal during the first few weeks of life. Babies of women who abuse drugs intravenously are at high risk of HIV infection.... pregnancy, drugs in

Prostaglandin Drugs

Synthetically produced prostaglandins.

Dinoprostone is used with oxytocin for induction of labour.

Gemeprost softens and helps to dilate the cervix prior to inducing an abortion.

Alprostadil is used to treat newborn infants awaiting surgery for some congenital heart diseases.... prostaglandin drugs

Psoralen Drugs

Drugs containing chemicals called psoralens, which occur in some plants and are present in some perfumes.

When absorbed into the skin, psoralens react with ultraviolet light to cause skin darkening or inflammation.

Psoralen drugs may be used in conjunction with ultraviolet light (a combination called PUVA) to treat psoriasis and vitiligo.

Overexposure to ultraviolet light during treatment, or to too high a dose of a psoralen drug, may cause redness and blistering of the skin.

Psoralens in perfumes may cause photosensitivity.... psoralen drugs

Psychotropic Drugs

Drugs that have an effect on the mind, including hallucinogenic drugs, sedative drugs, sleeping drugs, tranquillizer drugs, and antipsychotic drugs.... psychotropic drugs

Quinolone Drugs

A group of antibiotic drugs, often called antibacterials, that are used to treat bacterial infections. Quinolone drugs are derived from chemicals, rather than living organisms. Examples include norfloxacin, ciprofloxacin, and ofloxacin.

Quinolones are used in the treatment of a wide range of conditions, including urinary tract infections, acute diarrhoeal diseases (such as that caused by salmonella infections), and enteric fever. Their absorption is reduced by antacids containing magnesium and aluminium.

Quinolones should be used with caution in patients with epilepsy, during pregnancy and breast-feeding, and in children and adolescents. Side effects include nausea, vomiting, diarrhoea, headache, sleep disorders, dizziness, rash, and blood disorders.... quinolone drugs

Salicylate Drugs

A group of drugs, such as aspirin and benorilate, with antiinflammatory, fever-reducing, and mild analgesic action.

Overdose causes hyperventilation, tinnitus, sweating, abnormal bleeding, biochemical disturbances, and, in severe cases, convulsions and coma.... salicylate drugs

Sedative Drugs

A group of drugs used to produce sedation. Sedative drugs include sleeping drugs, antianxiety drugs, antipsychotic drugs, and some antidepressant drugs. A sedative drug is often included in a premedication.... sedative drugs

Sleeping Drugs

A group of drugs used to treat insomnia.

They include benzodiazepines, antihistamines, antidepressants, and chloral hydrate.

Sleeping drugs may cause drowsiness and impaired concentration on waking.

Long-term use may induce tolerance and dependence.... sleeping drugs

Sport, Drugs And

Four main types of drug are abused by athletes to enhance physical or mental condition.

Stimulants such as amfetamines can prevent fatigue and increase confidence.

Three types of hormone drugs may be abused: anabolic steroids (see steroids, anabolic) to speed muscle recovery after exercise; erythropoietin to boost the haemoglobin content of the blood, which may increase stamina; and growth hormone to stimulate muscle growth.

Analgesic drugs may be used to mask the pain of an injury.

Betablockers are taken to reduce tremor in sports that require a steady hand.

Aside from the health risks associated with abuse of these drugs, their use is prohibited in many competitive sports.... sport, drugs and

Steroid Drugs

A group of drugs including corticosteroid drugs and anabolic steroids (see steroids, anabolic).... steroid drugs

Stimulant Drugs

Drugs that increase brain activity by initiating the release of noradrenaline (norepinephrine).

Stimulants are of 2 types: central nervous system stimulants (for example, amfetamines), which increase alertness; and respiratory stimulants (see analeptic drugs), which encourage breathing.... stimulant drugs

Sulphonamide Drugs

A group of antibacterial drugs that has largely been superseded by more effective and less toxic alternatives.... sulphonamide drugs

Tetracycline Drugs

A group of antibiotic drugs commonly used to treat bronchitis, acne, syphilis, gonorrhoea, nongonococcal urethritis, and certain types of pneumonia.

If taken with milk, tetracyclines are not absorbed effectively into the intestines.

Possible side effects include nausea, vomiting, diarrhoea, worsening of kidney disorders, rash, and itching.

Tetracyclines may discolour developing teeth and are therefore not usually prescribed for children under age 12 or pregnant women.... tetracycline drugs

Thrombolytic Drugs

Sometimes called fibrinolytic drugs, this group of drugs is used to treat thrombosis, embolism, and myocardial infarction.

Thrombolytic drugs act within blood vessels to dissolve clots.

Possible adverse effects include abnormal bleeding and an allergic reaction.... thrombolytic drugs

Tranquillizer Drugs

Drugs that have a sedative effect. Tranquillizers are divided into 2 types: major tranquillizers (see antipsychotic drugs) and minor tranquillizers (see antianxiety drugs).... tranquillizer drugs

Vasodilator Drugs

A group of drugs that widen blood vessels.

Vasodilator drugs include ACE inhibitors, alphablockers, calcium channel blockers, nitrate drugs, and sympatholytic drugs.

They are used to treat disorders in which abnormal narrowing of blood vessels reduces blood flow through tissues, impairing the supply of oxygen.

Such disorders include angina pectoris and peripheral vascular disease.

Vasodilators are also used to treat hypertension and heart failure.

All vasodilator drugs may cause flushing, headaches, dizziness, fainting, and swollen ankles.... vasodilator drugs

Anti-tnf Drugs

see cytokine inhibitor.... anti-tnf drugs

Misuse Of Drugs Act 1971

(in the UK) an Act of Parliament restricting the use of dangerous drugs. These controlled drugs are divided into three classes: class A drugs (e.g. heroin, morphine and other potent opioid analgesics, cocaine, LSD) cause the most harm when misused; class B drugs include amphetamines, barbiturates, and cannabis, and class C drugs include most benzodiazepines and anabolic steroids. The Act specifies certain requirements for writing prescriptions for these drugs. The Misuse of Drugs (Supply to Addicts) Regulations 1997 and the Misuse of Drugs Regulations 2001 lay down who may supply controlled drugs and the rules governing their supply, prescription, etc.... misuse of drugs act 1971

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