A powerful analgesic which can be given under the tongue if nausea and vomiting are a problem.
Hyoscine butylbromide is used to relieve irritable bowel syndrome.
Hyoscine hydrobromide is used to control motion sickness and to reduce nausea in Ménière’s disease.
It is also used in eye-drops to dilate the pupil before an eye examination or surgery.
An injection of hyoscine hydrobromide is often given as part of a premedication because it dries secretions in the mouth and lungs.
Possible adverse effects of both forms include dry mouth, blurred vision, drowsiness, and constipation.... hyoscine
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 catechuThe 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
Normally, a young child requires a smaller dose than an adult. There are, however, other factors than age to be taken into consideration. Thus, children are more susceptible than adults to some drugs such as MORPHINE, whilst they are less sensitive to others such as ATROPINE. The only correct way to calculate a child’s dose is by reference to texts supplying a recommended dose in milligrams per kilogram. However, many reference texts simply quote doses for certain age-ranges.
Old people, too, often show an increased susceptibility to drugs. This is probably due to a variety of factors, such as decreased weight; diminished activity of the tissues and therefore diminished rate at which a drug is utilised; and diminished activity of the KIDNEYS resulting in decreased rate of excretion of the drug.
Weight and sex have both to be taken into consideration. Women require slightly smaller doses than men, probably because they tend to be lighter in weight. The e?ect of weight on dosage is partly dependent on the fact that much of the extra weight of a heavy individual is made up of fatty tissue which is not as active as other tissues of the body. In practice, the question of weight seldom makes much di?erence unless the individual is grossly over- or underweight.
Idiosyncrasy occasionally causes drugs administered in the ordinary dose to produce unexpected effects. Thus, some people are but little affected by some drugs, whilst in others, certain drugs – for example, psychoactive preparations such as sedatives – produce excessive symptoms in normal or even small doses. In some cases this may be due to hypersensitivity, or an allergic reaction, to the drug, which is a possibility that must always be borne in mind
(e.g. with PENICILLIN). An individual who is known to be allergic to a certain medication is strongly advised to carry a card to this e?ect, and always to inform medical and dental practitioners and/or a pharmacist before accepting a new prescription or buying an over-the-counter preparation.
Habitual use of a drug is perhaps the in?uence that causes the greatest increase in the dose necessary to produce the requisite e?ect. The classical example of this is with OPIUM and its derivatives.
Disease may modify the dose of medicines. This can occur in several ways. Thus, in serious illnesses the patient may be more susceptible to drugs, such as narcotics, that depress tissue activity, and therefore smaller doses must be given. Again, absorption of the drug from the gut may be slowed up by disease of the gut, or its e?ect may be enhanced if there is disease of the kidneys, interfering with the excretion of the drug.
Fasting aids the rapidity of absorption of drugs, and also makes the body more susceptible to their action. Partly for this reason, as well as to avoid irritation of the stomach, it is usual to prescribe drugs to be taken after meals, and diluted with water.
Combination of drugs is to be avoided if possible as it is often di?cult to assess what their combined e?ect may be. In some cases they may have a mutually antagonistic e?ect, which means that the patient will not obtain full bene?t. Sometimes a combination may have a deleterious e?ect.
Form, route and frequency of administration Drugs are now produced in many forms, though tablets are the most common and, usually, convenient. In Britain, medicines are given by mouth whenever possible, unless there is some degree of urgency, or because the drug is either destroyed in, or is not absorbed from, the gut. In these circumstances, it is given intravenously, intra-muscularly or subcutaneously. In some cases, as in cases of ASTHMA or BRONCHITIS, the drug may be given in the form of an inhalant (see INHALANTS), in order to get the maximum concentration at the point where it is wanted: that is, in the lungs. If a local e?ect is wanted, as in cases of diseases of the skin, the drug is applied topically to the skin. In some countries there is a tendency to give medicines in the form of a suppository which is inserted in the rectum.
Recent years have seen developments whereby the assimilation of drugs into the body can be more carefully controlled. These include, for example, what are known as transdermals, in which drugs are built into a plaster that is stuck on the skin, and the drug is then absorbed into the body at a controlled rate. This method is now being used for the administration of GLYCERYL TRINITRATE in the treatment of ANGINA PECTORIS, and of hyoscine hydrobromide in the treatment of MOTION (TRAVEL) SICKNESS. Another is a new class of implantable devices. These are tiny polymers infused with a drug and implanted just under the skin by injection. They can be tailored so as to deliver drugs at virtually any rate – from minutes to years. A modi?cation of these polymers now being investigated is the incorporation of magnetic particles which allow an extra burst of the incorporated drug to be released in response to an oscillating magnetic ?eld which is induced by a magnetic ‘watch’ worn by the patient. In this way the patient can switch on an extra dose of drug when this is needed: insulin, for instance, in the case of diabetics. In yet another new development, a core of drug is enclosed in a semi-permeable membrane and is released in the stomach at a given rate. (See also LIPOSOMES.)... dosage
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