Placebo medicines

A placebo" is any component of therapy that is without specific biological activity for the condition being treated.

Placebo medicines are used for two purposes:

• As a control in scientific evaluation of drugs (see Therapeutic trials) (see p. 60)

• To benefit or please a patient, not by any pharmacological actions, but by psychological means.

All treatments have a psychological component, whether to please (placebo effect) or, occasionally, to vex (negative placebo or nocebo56 effect).

A placebo medicine is a vehicle for 'cure' by suggestion, and is surprisingly often successful, if only temporarily.57 All treatments carry placebo effect: physiotherapy, psychotherapy, surgery, entering a patient into a therapeutic trial, even the personality and style of the doctor; but the effect is most easily investigated with drugs, for the active and the inert can often be made to appear identical so that comparisons can be made.

The deliberate use of drugs as placebos is a confession of failure by the doctor. Failures however are sometimes inevitable and an absolute condemnation of the use of placebos on all occasions would be unrealistic.

55 Latin: placebo, I shall be pleasing or acceptable.

56 Latin: nocebo, I shall injure; the term is little used.

A placebo-reactor is an individual who reports changes of physical or mental state after taking a pharmacologically inert substance.

Placebo-reactors are suggestible people and likely to respond favourably to any treatment. They have misled doctors into making false therapeutic claims.

Negative reactors, who develop adverse effects when given a placebo, exist but, fortunately, are fewer.

Some 35% of the physically ill and 40% or more of the mentally ill respond to placebos. Placebo reaction is an inconstant attribute; a person may respond at one time in one situation and not at another time under different conditions. There is some consistency in the type of person who tends to react to any therapeutic intervention. In one study on medical students, psychological tests revealed that those who reacted to a placebo tended to be extraverted, sociable, less dominant, less self-confident, more appreciative of their teaching, more aware of their autonomic functions and more neurotic than their colleagues who did not react to a placebo under the particular conditions of the experiment.

It is of great importance that all who administer drugs should be aware that their attitudes to the treatment may greatly influence the result. Undue scepticism may prevent a drug from achieving its effect and enthusiasm or confidence may potentiate the actions of drugs.

57 As the following account by a mountain rescue guide illustrates: 'The incident involved a 15-year-old boy who sustained head injuries and a very badly broken leg. Helicopter assistance was unavailable and therefore we had to carry him by stretcher to the nearest landrover (several miles away) and then on to a waiting ambulance.

During this long evacuation the boy was in considerable distress and we administered Entonox (a mixture of nitrous oxide and oxygen, 50% each) sparingly as we only had one small cylinder. He repeatedly remarked how much better he felt after each intake of Entonox (approximately every 20 minutes) and after 7 hours or so we eventually got him safely into the ambulance and on his way to hospital.

On going to replace the Extonox we discovered the cylinder was still full of gas due to the equipment being faulty. There was no doubt that the boy felt considerable pain relief as a result of thinking he was receiving Entonox.'

Tonics are placebos. They may be defined as substances with which it is hoped to strengthen and increase the appetite of those so weakened by disease, misery, overindulgence in play or work, or by physical or mental inadequacy, that they cannot face the stresses of life. The essential feature of this weakness is the absence of any definite recognisable defect for which there is a known remedy. Since tonics are placebos, they must be harmless.58

Pharmacoeconomics

Even the richest societies cannot satisfy the appetite of their citizens for health care based on their real needs, on their wants and on their (often unrealistic) expectations.

Health care resources are rationed59 in one way or another, whether according to national social policies or to individual wealth. The debate on supply is not about whether there should be rationing, but about what form rationing should take; whether it should be explicit or concealed (from the public).

Doctors prescribe, patients consume and, increasingly throughout the world, third (purchasing) parties (government, insurance companies) pay the bill with money they have obtained from increasingly reluctant healthy members of the public.

The purchasers of health care are now engaged in serious exercises to contain drug costs in the short term without, it is hoped, impairing the quality of medical care, or damaging the development of useful new drugs (which is an enormously expensive and long-term process). This can be achieved successfully only if reliable data are available on costs and benefits, both absolute and relative. The difficulties of generating such data, not only during development, but later under actual-use conditions, are enormous and are addressed by a special breed of professionals: the health economists.

58 Tonics (licensed) available in the UK include: Gentian Mixture, acid (or alkaline) (gentian, a natural plant bitter substance, and dilute HCl or sodium bicarbonate): Labiton (thiamine, caffeine, alcohol, all in low dose).

59 The term rationing is used here to embrace the allocation of priorities as well as the actual withholding of resources (in this case, drugs).

Economics is the science of the distribution of wealth and resources. Prescribing doctors, who have a duty to the community .is well as to individual patients, cannot escape involvement with economics.

The economists' objective

The objective is to enable needs to be defined so that available resources may be deployed according to priorities set by society, which has an interest in fairness between its members. The question is whether resources are to be distributed in accordance with and unregulated power struggle between professionals and associations of patients and public pressure groups — all, no doubt, warm-hearted towards deserving cases of one kind or another, but none able to view the whole scene; or whether there is to be a planned evaluation that allows division of the resources on the basis of some visible attempt at fairness.

A health economist60 writes:

The economist's approach to evaluating drug therapies is to look at a group of patients with a particular disorder and the various drugs that could be used to treat them. The costs of the various treatments and some costs associated with their use (together with the costs of giving no treatment) are then considered in terms of impact on health status (survival and quality of life) and impact on other health care costs (e.g. admissions to hospital, need for other drugs, use of other procedures).

Economists are often portrayed as people who want to focus on cost, whereas in reality they see everything in terms of a balance between costs and benefits.

Four economic concepts have particular importance to the thinking of every doctor who takes up a pen to prescribe, i.e. to distribute resources.

• Opportunity cost means that which has to be sacrificed in order to carry out a certain course of action, i.e. costs are benefits foregone elsewhere. If money is spent on prescribing, that money is not available for another purpose; wasteful prescribing can be seen as an affront to those

60 Prof Michael Drummond.

who are in serious need, e.g. institutionalised mentally handicapped citizens who everywhere would benefit from increased resources.

• Cost-effectiveness analysis is concerned with how to attain a given objective at minimum financial cost, e.g. prevention of postsurgical venous thromboembolism by heparins, warfarin, aspirin, external pneumatic compression. Analysis includes cost of: materials, adverse effects, any tests, nursing and doctor time, duration of stay in hospital (which may greatly exceed the cost of the drug).

• Cost-benefit analysis is concerned with issues of whether (and to what extent) to pursue objectives and policies; it is thus a broader activity than cost-effectiveness analysis and puts monetary values on the quality as well as on the quantity (duration) of life.

• Cost-utility analysis is concerned with comparisons between programmes, e.g. an antenatal drug treatment which saves a young life or a hip replacement operation which improves mobility in a man of 60 years. Such differing outcomes can be placed on the same basis for comparison by computing quality-adjusted life years (see below).

An allied measure is the cost-minimisation analysis which finds the least costly programme among those shown or assumed to be of equal benefit. Economic analysis requires that both quantity and quality of life be measured. The former is easy, the latter is hard.

Quality of life

Everyone is familiar with the measurement of the benefit of treatment in saving or extending life, i.e. life expectancy: the measure is the quantity of life (in years). But it is evident that life may be extended and yet have a low quality, even to the point that it is not worth having at all. It is therefore useful to have a unit of health measurement that combines the quality of life with its quality to allow individual and social decisions to be made on a sounder basis than mere intuition. To meet this need economists have developed the quality-adjusted-life-year (QALY); estimations of years of life expectancy are modified according to estimations of quality of life.

Quality of life has four principal dimensions:61

1. physical mobility

2. freedom from pain and distress

3. capacity for self-care

4. ability to engage in normal work and social interactions.

The approach to measure quality of life has been developed by questionnaire to measure what the subject perceives as personal health. The assessments are being refined to provide improved assessment of the benefits and risks of medicines to the individual and to society. The challenge is to ensure that these are sufficiently robust to make resource allocation decisions between, for example: the rich and the poor, the educated and the uneducated, the old and the young, as well as between groups of patients having very different diseases. Plainly, quality of life is a major aspect of what is called outcomes research.

Self-medication

To feel unwell is common, though the frequency varies with social and cultural circumstances. People commonly experience symptoms or complaints and commonly want to take remedial action. In one study of adults randomly selected from a large population, 9 out of 10 had one or more complaints in the 2 weeks before interview; in another of premenopausal women a symptom occurred as often as 1 day in 3; in both studies a medicine was taken for more than half these occurrences.

Increasingly, educated and confident consumers are aware of five consumer rights (United Nations charter):

• access (to a wide range of products)

• choice (self-determination)

• information (on which to base choice)

• redress (when things go wrong)

• safety (appropriate to the use of the product).

61 Williams A1983. In: Smith G T (ed) Measuring the social benefits of medicine. Office of Health Economics, London.

Modern consumers (patients) wish to take a greater role in the maintenance of their own health and are often competent to manage (uncomplicated) chronic and recurrent illnesses (not merely short-term symptoms) after proper medical diagnosis and with only occasional professional advice, e.g. use of histamine H2-receptor blocker, topical corticosteroid and antifungal, and oral contraceptive. They are understandably unwilling to submit to the inconvenience of visiting a doctor for what they rightly feel they can manage for themselves, given adequate information.

Increased consumer autonomy leads to satisfied:

• governments (lower drug bill)

The pharmaceutical industry enthusiastically estimates that extending the use of self-medication to all potentially self-treatable illnesses could save 100-150 million general practitioner consultations per year (in the UK: population 57 million). But there will also be added costs as pharmacists extend their responsibilities for supply and information.

Regulatory authorities are increasingly receptive to switching hitherto prescription-only medicines (POM) for self-medication (over-the-counter, OTC, sale) via pharmacies (P) or via any retail outlet (general sale). The operation is known as POM-OTC or POM-P 'switch'. It requires particularly exacting standards of safety.

• short-term relief of symptoms where accurate diagnosis is unnecessary

• uncomplicated cases of some chronic and recurrent disease (a medical diagnosis having been made and advice given).

Safety in self-medication (an overriding requirement) depends on four items:

• The drug — its inherent properties, dose and duration of use, including its power to induce dependence

• The formulation — devised with unsupervised use in mind, e.g. low dose

• Information — available with all purchases (printed) and rigorously reviewed (by panels of potential users) for user-friendliness and adequacy for a wide range of education and intellectual capacity

• Patient compliance.

Doctors must recognise the increasing importance of questioning about self-medication when taking a drug history.

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Blood Pressure Health

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