Drugs 13: 225-22911977} iCI ADIS Press 1977
Drug Treatment in the Elderly: Problems and Prescribing Rules Robin H. Briant Auckland Hospital , Auckland
Old people are recorded in several surveys as having more drug reactions than their younger counterparts. The term drug reaction covers all unwanted effects of drugs; hypersensitivity, toxicity, or the extension of known pharmacological properties. It is estimated that about 80 % of unwanted drug effects are of this last variety; they are totally predictable and to a considerable extent avoidable. For example, excessive hypoglycaemia is a predictable response to an excessive dose of insulin - an extension of its therapeutic effect. Similarly, anticholinergic properties are an integral feature of currently available tricyclic antidepressants which will produce dry mouth, changes in pupillary activity, changes in bladder sphincter function and some sedation, in almost everyone. Whether or not the effects are troublesome to the patient depends upon many variables - the dose, the levels of drug achieved, the presence of disease or other drugs, and the general awareness and tolerance of the patient. The features in the elderly population which make them the current bearer of many iII-effects will be discussed (table I),
J. Extent of Drug Morbidity in the Elderly There is no good study to show the extent and seriousness of this problem in elderly people, but an example will serve to set the scene. This is a report of 236 consecutive patients admitted to an Australian psychogeriatric unit, of whom 37 (16 % ) were suffering the direct effect of psychotherapeutic medication (Learoyd, 1972). Seven patients were excessively sedated or confused; 16 had hypotensive episodes producing falls and fractures, 14 had behaviour disturbances. All improved and were discharged from hospital when their medication was stopped or significantly reduced.
2. Is the Elderly Person in Some Way Pharmacologically Incompetent? 2.1 Drug Metabolism It is often stated that the elderly cannot metabolise drugs efficiently. This statement owes more to folk-
226
Drug Treatment in the Elderly
Table I. A summary of drug problems for the elderly pa-
tient 1. Difficulty keeping to planned regimens ; e.g. fo rgetfulness, bad eyesight.
test drug in plasma increased with the number of drugs taken (Wallace et al.. 1976).
2.4 'Sensitivity' to Drugs
2. Excessive numbers of drugs prescr ibed . 3 . Undue ' sensiti vity' to drug effects. 4 . Many unwanted drug effects.
lore than to hard fact. for although some elderly. people have been shown to be slow metabolisers, this is not a general feature. If the elderly patient has normal hepatic function his rate of drug metabolism is likely to be comparable with that of a younger adult.
2.2 Drug Excretion One functional decline that does occur consistently with age is in glomerular filtration rate which. after the age of 65, is likely to be less than two-thirds that of a young adult. a change that may not be reflected in plasma urea or creatinine. Thus. drugs which are mainly excreted by the kidney without prior metabolism will persist for longer and in higher concentrations in blood and tissues in the elderly patient. The important drugs in this category are digoxin, chlorpropamide. the penicillins and the aminoglycoside antibiotics.
One frequently recorded statement is that the elderly are unduly sensitive to the effects of drugs . This observation is difficult to reduce to its pharmacological elements - receptor sensitivity - for that is not a measurable parameter in intact man. It is an ill-defined sensitivity, which may be broadly compared with the excessivesensitivity of the brain of patients with hepatic failure to the effects of morphine - an observation not explained by changes in the ability to metabolise the opiate. Thus. one may envisage the elderly patient treated for high blood pressure (which mayor may not warrant lowering) with a powerful antihyperten sive agent and a diuretic. There may well be sedation and a troublesome dry mouth, with the development of debilitating dizziness on standing . a postural hypotension which is exaggerated by diuretic-induced fluid loss and by slowly responding vascular reflexes. In the mental confusion so induced. the elderly person may become quite unable to care for himself. and eventually a fall or faint necessitates hospital admission or institut ional care. The elderly have often suffered an enormous decline in functional capacity of brain and other organ systems. and many are very precariously balanced between living independently and not doing so. A fairly small insult may suffice to shift that balance, and such an insult can be produced by drugs .
2.3 Drug Absorption and Distribution Absorption . distribution or protein binding of drugs may vary with the individual or disease. but are not consistently abnormal in old people. One recent study however, showed that protein binding of several drugs was significantly altered in elderly subjects receiving multiple drug therap y - the amount of unbound (and therefore pharmacologically active)
3 . Are There Problems for the Elderly Patient in Taking Medication? People of all ages tend to forget or purposely ignore their medication. Medication errors have been estimated as occurring in about 60 % of elderly people with chron ic disease who live at home. In one reported survey. the likelihood of these errors occur-
Drug Treatment in the Elderly
ring was greater if 3 or more medicines were taken, and 26 % of the errors made were classified as potentially serious. Forgetfulness is one of the real problems of ageing and is at the basis of much of the medication problem. But there is the additional difficulty of learning new things - such as regular pill taking - perhaps with such compounding problems as inability to read the label on the pill bottle. The patient thus has no way of identifying the contents except as 'little white pills.' Imagine trying to sort out the contents of confused bottles of digoxin, frusemide, colchicine, diazepam and clonidine, and imagine the chaos and disaster that would occur if such bottles were indeed confused. Elderly patients must be given every possible assistance in taking their drugs accurately. This means explanations from the prescribing doctor and the chemist, clearly written labels with lettering large enough for the individual to read. District nurse , relatives or neighbours may need to oversee the medication , using reminder systems such as a check list, or a row of eggcups with the pills for different times of the day set out as first morning duty . Such a system helps to keep track of what is happening and tends to prevent the taking of too many doses per day.
4. Special Areas oj Difficulty with Drugs
227
icity may not be suspected on clinical grounds , whilst plasma digoxin assays may show levels 4 to 7 nmols/litre (toxicity is associated with levels over 2.6 nmol/Iitre). Plasma digoxin assay is not widely available, is expensive and time consuming for the laboratory. Rather than rely upon the test, it is better simply to discontinue the drug and observe the patient for a period (it may take a week to reduce toxic levels to therapeutic), and reassess the diagnosis - it may not even be necessary to restart the drug. The paediatric-geriatric (PG) Lanoxin tablets containing O.0625mg of digoxin provide a great deal of dose flexibilityand are most satisfactory in the elderly population .
4.2 Diuretics Thiazides and potent natriuretic agents may be associated with increasing digoxin toxicity, by virtue of their potassium-losing effects. Alternatively, the potassium-sparing diuretics may induce dangerous hyperkalaemia where impairment of renal function exists. Whichever type of diuretic is used, the indications for its use should be clear, the need for its continuation reassessed frequently, and the serum potassium monitored regularly.
4.1 Digoxin 4.3 Antihypertensive Agents This drug is prescribed for a large number of elderly people. It is probably overused, and certainly produces a large amount of morbidity and some deaths . The margin for error is small , differences in bioavailability of different formulations have led to confusion over the 'right' dose, and the decline in glomerular filtration rate with age makes it a very difficult drug to use. The clinical evidence of digoxin toxicity in the elderly is often very subtle - vague loss of well-being, appetite and mobility. Many elderly patients are admitted to medical wards in this state and the diagnosis of digoxin tox-
The definition of hypertension and who should be treated is particularly difficult in the elderly. The decision to treat or not to treat must be made by the doctor for each individual patient. Accelerated-phase hypertension, angina, heart failure, transient cerebral ischaemia or falling renal function, are all strong indications for therapy. In the asymptomatic milder case, one should have a clear idea of therapeutic goals before initiating antihypertensive agents, for the blood pressure may be lowered only at the cost of severe drug-induced morbidity .
Drug Treatment in the Elderly
4.4
~-Adrenoceptor
Blocking Agents
These compounds are very beneficial to many people, in relieving or reducing angina and in hypertension , but once again they carry a real risk of making more ill-health than they relieve. Most doctors are well aware that impaired cardiac function may be converted to frank heart failure by ~-blockade ; but it is less well appreciated that severe asthma can be precipitated in people who have been asthma-free for many years or who suffer only mild chronic obstructive airways disease.
4.5 Oral Hypoglycaemic Agents
228
Powerful anti-inflammatory agents such as indomethacin or phenylbutazone have a high rate of adverse effects. but it may be considered that their benefit-to-hazard ratio is still worthwhile. As a general rule. a move to opiate-related cornpounds for chronic conditions is not justified. Remember that codeine produces troublesome constipation which will be particularly unacceptable in a generation already somewhat obsessed by bowel habit; propoxyphene makes many people nauseated; and pentazocine can produce unpleasant psychiatric symptoms.
4.7 The Management of Depression and Insomnia
Many elderly people complain of sleeplessness and Diabetes beginning in the elderly is usually associdepression. symptoms which may be referrable to ated with obesity and is often asymptomatic. The first line of treatment is diet to reduce total caloric intake pain. limitation . bereavement and loneliness. It is exand total body mass. The likelihood that oral hy- tremely difficult for the general doctor to identify poglycaemic agents will make the patient feel better, which patients will benefit from antidepressant or that they will improve morbidity or mortality is medication especially when many compounding facvery low. Prolonged or recurrent hypoglycaemia is a tors seem to be irreversible. All possible social supreal and very dangerous potential result of the use of port should be offered in the first instance. If a positive diagnosis of depressive illness is made, specific these drugs. antidepressant drugs may be given, remembering that anticholinergic and sedative side-effects may be in4.6 The Management of Pain and Inflammation tolerable in some patients. Careful manipulation of the regimen to provide most. or all ofthe daily dose at Degenerative joint disease. with or without in- bedtime. may limit unpleasant side-effects and allow flammation, is an important source of disability and the drug a chance to achieve therapeutic success. pain in the elderly, and its management should be It is important to remember that the taken very seriously. As in all fields of rheumatic dis- benzodiazepine compounds are anxiolytics not antiease, the programme should be to begin with simple depressants , and should be used only for the specific drugs in optimum doses. titrated against the patient's indication of anxiety, not to elevate mood. response and side-effects. Too often one sees effective The reduction in physical activity that accomdrugs used in small, sub-therapeutic doses. panies old age. reduces the sleep requirement. and the Aspirin for anti-inflammatory and analgesic addition of pain, breathlessness or depression will effect. or paracetamol for analgesia alone are the make sleep even more elusive. Effort should be cheapest and among the safest available. Gastroin- directed toward eliminating these 'wakening' intestinal irritation may be the limiting factor with fluences and gaining acceptance of an altered sleep aspirin , necessitating the use of newer anti-inflam- pattern. All available hypnotic drugs (with the excepmatory compounds which seem to cause rather less tion of a small dose of ethanol) have prolonged effects of this problem, such as ibuprofen or ketoprofen. with hangover and sedation well into the next day.
229
Drug Treatment in the Elderly
Table 1/. Prescribing rules in the elderly
1. Have a clear and rational therapeutic goal, preferably based on sound diagnosis. 2. Review all medications taken to identify potential interactions and to eliminate drugs no longer needed. 3. Devise a regimen which is simple, appropriate to the patient's life-style, and which provides the optimum dose of the safest compound . 4. Make sure the patient understands the treatment programme, can read the medication labels and is competent to be in charge of his own drug-taking. 5. Stop any drug that is not necessary.
5. Drug Use in the Elderly: The Problem and its Solution Stated simply. the problem is that the elderly have a great deal of pathology and a great number of symptoms. and therefore they present very frequently to doctors . The desire of doctors to relieve suffering and the availability of a large number of powerful drugs , make for a situation of excessive drug use. And because so many of the disorders of old age are not amenable to drug treatment. the end result is that unwanted drug effects are added to the basic disability. The solution depends upon doctors and patients. Doctors must define reasonable and rational therapeutic aims and must convince patients that drugs are inappropriate in many situations . They
must use non-drug therapy wherever possible and appropriate. and use drugs wisely and sparingly. They must keep alert for the emergence of unwanted drug effects and always be ready to stop unnecessary or possibly harmful drugs. All regimens should be kept as simple as possible; verbal instructions should be unambiguous and written ones legible,and pill bottles also labelled so that they can be read. The assistance of practice-nurse, district nurse, neighbour or relative should be invoked to assist the elderly patient in establishing a pill-taking regimen that is acceptableand successful. A summary of prescribing rules in the elderly is given in table II. The author believes that doctors are too uncritical of their therapeutic endeavours and believe too much in the beneficial effects of medicine. Doctors must be prepared to acknowledge a given condition or patient does not require, and will not benefit from, available therapy, and that therapy should therefore not be given. And they must remember that use of a drug may be associated with, but not responsible for, relief of symptoms or resolution of disease.
References Learoyd, B.M.: Psychotropic drugs and the elderly patient. Medical Journal of Australia I: 1131 -1133 (972). Wallace. S.; Whiting. B. and Runcie, J.: Factors affecting drug binding in plasma of elderly patients. British Journal of Clinical Pharmacology 3: 327-330 (976).
Author's address: Dr Robin H. Briant, Department of Medicine. University of Auckland School of Medicine. Park Road. Auckland 3 (New Zealand).
Drug Treatment in the Elderly: Problems and Prescribing Rules Robin H. Briant Auckland Hospital , Auckland
Old people are recorded in several surveys as having more drug reactions than their younger counterparts. The term drug reaction covers all unwanted effects of drugs; hypersensitivity, toxicity, or the extension of known pharmacological properties. It is estimated that about 80 % of unwanted drug effects are of this last variety; they are totally predictable and to a considerable extent avoidable. For example, excessive hypoglycaemia is a predictable response to an excessive dose of insulin - an extension of its therapeutic effect. Similarly, anticholinergic properties are an integral feature of currently available tricyclic antidepressants which will produce dry mouth, changes in pupillary activity, changes in bladder sphincter function and some sedation, in almost everyone. Whether or not the effects are troublesome to the patient depends upon many variables - the dose, the levels of drug achieved, the presence of disease or other drugs, and the general awareness and tolerance of the patient. The features in the elderly population which make them the current bearer of many iII-effects will be discussed (table I),
J. Extent of Drug Morbidity in the Elderly There is no good study to show the extent and seriousness of this problem in elderly people, but an example will serve to set the scene. This is a report of 236 consecutive patients admitted to an Australian psychogeriatric unit, of whom 37 (16 % ) were suffering the direct effect of psychotherapeutic medication (Learoyd, 1972). Seven patients were excessively sedated or confused; 16 had hypotensive episodes producing falls and fractures, 14 had behaviour disturbances. All improved and were discharged from hospital when their medication was stopped or significantly reduced.
2. Is the Elderly Person in Some Way Pharmacologically Incompetent? 2.1 Drug Metabolism It is often stated that the elderly cannot metabolise drugs efficiently. This statement owes more to folk-
226
Drug Treatment in the Elderly
Table I. A summary of drug problems for the elderly pa-
tient 1. Difficulty keeping to planned regimens ; e.g. fo rgetfulness, bad eyesight.
test drug in plasma increased with the number of drugs taken (Wallace et al.. 1976).
2.4 'Sensitivity' to Drugs
2. Excessive numbers of drugs prescr ibed . 3 . Undue ' sensiti vity' to drug effects. 4 . Many unwanted drug effects.
lore than to hard fact. for although some elderly. people have been shown to be slow metabolisers, this is not a general feature. If the elderly patient has normal hepatic function his rate of drug metabolism is likely to be comparable with that of a younger adult.
2.2 Drug Excretion One functional decline that does occur consistently with age is in glomerular filtration rate which. after the age of 65, is likely to be less than two-thirds that of a young adult. a change that may not be reflected in plasma urea or creatinine. Thus. drugs which are mainly excreted by the kidney without prior metabolism will persist for longer and in higher concentrations in blood and tissues in the elderly patient. The important drugs in this category are digoxin, chlorpropamide. the penicillins and the aminoglycoside antibiotics.
One frequently recorded statement is that the elderly are unduly sensitive to the effects of drugs . This observation is difficult to reduce to its pharmacological elements - receptor sensitivity - for that is not a measurable parameter in intact man. It is an ill-defined sensitivity, which may be broadly compared with the excessivesensitivity of the brain of patients with hepatic failure to the effects of morphine - an observation not explained by changes in the ability to metabolise the opiate. Thus. one may envisage the elderly patient treated for high blood pressure (which mayor may not warrant lowering) with a powerful antihyperten sive agent and a diuretic. There may well be sedation and a troublesome dry mouth, with the development of debilitating dizziness on standing . a postural hypotension which is exaggerated by diuretic-induced fluid loss and by slowly responding vascular reflexes. In the mental confusion so induced. the elderly person may become quite unable to care for himself. and eventually a fall or faint necessitates hospital admission or institut ional care. The elderly have often suffered an enormous decline in functional capacity of brain and other organ systems. and many are very precariously balanced between living independently and not doing so. A fairly small insult may suffice to shift that balance, and such an insult can be produced by drugs .
2.3 Drug Absorption and Distribution Absorption . distribution or protein binding of drugs may vary with the individual or disease. but are not consistently abnormal in old people. One recent study however, showed that protein binding of several drugs was significantly altered in elderly subjects receiving multiple drug therap y - the amount of unbound (and therefore pharmacologically active)
3 . Are There Problems for the Elderly Patient in Taking Medication? People of all ages tend to forget or purposely ignore their medication. Medication errors have been estimated as occurring in about 60 % of elderly people with chron ic disease who live at home. In one reported survey. the likelihood of these errors occur-
Drug Treatment in the Elderly
ring was greater if 3 or more medicines were taken, and 26 % of the errors made were classified as potentially serious. Forgetfulness is one of the real problems of ageing and is at the basis of much of the medication problem. But there is the additional difficulty of learning new things - such as regular pill taking - perhaps with such compounding problems as inability to read the label on the pill bottle. The patient thus has no way of identifying the contents except as 'little white pills.' Imagine trying to sort out the contents of confused bottles of digoxin, frusemide, colchicine, diazepam and clonidine, and imagine the chaos and disaster that would occur if such bottles were indeed confused. Elderly patients must be given every possible assistance in taking their drugs accurately. This means explanations from the prescribing doctor and the chemist, clearly written labels with lettering large enough for the individual to read. District nurse , relatives or neighbours may need to oversee the medication , using reminder systems such as a check list, or a row of eggcups with the pills for different times of the day set out as first morning duty . Such a system helps to keep track of what is happening and tends to prevent the taking of too many doses per day.
4. Special Areas oj Difficulty with Drugs
227
icity may not be suspected on clinical grounds , whilst plasma digoxin assays may show levels 4 to 7 nmols/litre (toxicity is associated with levels over 2.6 nmol/Iitre). Plasma digoxin assay is not widely available, is expensive and time consuming for the laboratory. Rather than rely upon the test, it is better simply to discontinue the drug and observe the patient for a period (it may take a week to reduce toxic levels to therapeutic), and reassess the diagnosis - it may not even be necessary to restart the drug. The paediatric-geriatric (PG) Lanoxin tablets containing O.0625mg of digoxin provide a great deal of dose flexibilityand are most satisfactory in the elderly population .
4.2 Diuretics Thiazides and potent natriuretic agents may be associated with increasing digoxin toxicity, by virtue of their potassium-losing effects. Alternatively, the potassium-sparing diuretics may induce dangerous hyperkalaemia where impairment of renal function exists. Whichever type of diuretic is used, the indications for its use should be clear, the need for its continuation reassessed frequently, and the serum potassium monitored regularly.
4.1 Digoxin 4.3 Antihypertensive Agents This drug is prescribed for a large number of elderly people. It is probably overused, and certainly produces a large amount of morbidity and some deaths . The margin for error is small , differences in bioavailability of different formulations have led to confusion over the 'right' dose, and the decline in glomerular filtration rate with age makes it a very difficult drug to use. The clinical evidence of digoxin toxicity in the elderly is often very subtle - vague loss of well-being, appetite and mobility. Many elderly patients are admitted to medical wards in this state and the diagnosis of digoxin tox-
The definition of hypertension and who should be treated is particularly difficult in the elderly. The decision to treat or not to treat must be made by the doctor for each individual patient. Accelerated-phase hypertension, angina, heart failure, transient cerebral ischaemia or falling renal function, are all strong indications for therapy. In the asymptomatic milder case, one should have a clear idea of therapeutic goals before initiating antihypertensive agents, for the blood pressure may be lowered only at the cost of severe drug-induced morbidity .
Drug Treatment in the Elderly
4.4
~-Adrenoceptor
Blocking Agents
These compounds are very beneficial to many people, in relieving or reducing angina and in hypertension , but once again they carry a real risk of making more ill-health than they relieve. Most doctors are well aware that impaired cardiac function may be converted to frank heart failure by ~-blockade ; but it is less well appreciated that severe asthma can be precipitated in people who have been asthma-free for many years or who suffer only mild chronic obstructive airways disease.
4.5 Oral Hypoglycaemic Agents
228
Powerful anti-inflammatory agents such as indomethacin or phenylbutazone have a high rate of adverse effects. but it may be considered that their benefit-to-hazard ratio is still worthwhile. As a general rule. a move to opiate-related cornpounds for chronic conditions is not justified. Remember that codeine produces troublesome constipation which will be particularly unacceptable in a generation already somewhat obsessed by bowel habit; propoxyphene makes many people nauseated; and pentazocine can produce unpleasant psychiatric symptoms.
4.7 The Management of Depression and Insomnia
Many elderly people complain of sleeplessness and Diabetes beginning in the elderly is usually associdepression. symptoms which may be referrable to ated with obesity and is often asymptomatic. The first line of treatment is diet to reduce total caloric intake pain. limitation . bereavement and loneliness. It is exand total body mass. The likelihood that oral hy- tremely difficult for the general doctor to identify poglycaemic agents will make the patient feel better, which patients will benefit from antidepressant or that they will improve morbidity or mortality is medication especially when many compounding facvery low. Prolonged or recurrent hypoglycaemia is a tors seem to be irreversible. All possible social supreal and very dangerous potential result of the use of port should be offered in the first instance. If a positive diagnosis of depressive illness is made, specific these drugs. antidepressant drugs may be given, remembering that anticholinergic and sedative side-effects may be in4.6 The Management of Pain and Inflammation tolerable in some patients. Careful manipulation of the regimen to provide most. or all ofthe daily dose at Degenerative joint disease. with or without in- bedtime. may limit unpleasant side-effects and allow flammation, is an important source of disability and the drug a chance to achieve therapeutic success. pain in the elderly, and its management should be It is important to remember that the taken very seriously. As in all fields of rheumatic dis- benzodiazepine compounds are anxiolytics not antiease, the programme should be to begin with simple depressants , and should be used only for the specific drugs in optimum doses. titrated against the patient's indication of anxiety, not to elevate mood. response and side-effects. Too often one sees effective The reduction in physical activity that accomdrugs used in small, sub-therapeutic doses. panies old age. reduces the sleep requirement. and the Aspirin for anti-inflammatory and analgesic addition of pain, breathlessness or depression will effect. or paracetamol for analgesia alone are the make sleep even more elusive. Effort should be cheapest and among the safest available. Gastroin- directed toward eliminating these 'wakening' intestinal irritation may be the limiting factor with fluences and gaining acceptance of an altered sleep aspirin , necessitating the use of newer anti-inflam- pattern. All available hypnotic drugs (with the excepmatory compounds which seem to cause rather less tion of a small dose of ethanol) have prolonged effects of this problem, such as ibuprofen or ketoprofen. with hangover and sedation well into the next day.
229
Drug Treatment in the Elderly
Table 1/. Prescribing rules in the elderly
1. Have a clear and rational therapeutic goal, preferably based on sound diagnosis. 2. Review all medications taken to identify potential interactions and to eliminate drugs no longer needed. 3. Devise a regimen which is simple, appropriate to the patient's life-style, and which provides the optimum dose of the safest compound . 4. Make sure the patient understands the treatment programme, can read the medication labels and is competent to be in charge of his own drug-taking. 5. Stop any drug that is not necessary.
5. Drug Use in the Elderly: The Problem and its Solution Stated simply. the problem is that the elderly have a great deal of pathology and a great number of symptoms. and therefore they present very frequently to doctors . The desire of doctors to relieve suffering and the availability of a large number of powerful drugs , make for a situation of excessive drug use. And because so many of the disorders of old age are not amenable to drug treatment. the end result is that unwanted drug effects are added to the basic disability. The solution depends upon doctors and patients. Doctors must define reasonable and rational therapeutic aims and must convince patients that drugs are inappropriate in many situations . They
must use non-drug therapy wherever possible and appropriate. and use drugs wisely and sparingly. They must keep alert for the emergence of unwanted drug effects and always be ready to stop unnecessary or possibly harmful drugs. All regimens should be kept as simple as possible; verbal instructions should be unambiguous and written ones legible,and pill bottles also labelled so that they can be read. The assistance of practice-nurse, district nurse, neighbour or relative should be invoked to assist the elderly patient in establishing a pill-taking regimen that is acceptableand successful. A summary of prescribing rules in the elderly is given in table II. The author believes that doctors are too uncritical of their therapeutic endeavours and believe too much in the beneficial effects of medicine. Doctors must be prepared to acknowledge a given condition or patient does not require, and will not benefit from, available therapy, and that therapy should therefore not be given. And they must remember that use of a drug may be associated with, but not responsible for, relief of symptoms or resolution of disease.
References Learoyd, B.M.: Psychotropic drugs and the elderly patient. Medical Journal of Australia I: 1131 -1133 (972). Wallace. S.; Whiting. B. and Runcie, J.: Factors affecting drug binding in plasma of elderly patients. British Journal of Clinical Pharmacology 3: 327-330 (976).
Author's address: Dr Robin H. Briant, Department of Medicine. University of Auckland School of Medicine. Park Road. Auckland 3 (New Zealand).
