Placebo tribulations

Charles Weijer has elegantly discussed the ethical issues regarding the use of placebo controls in clinical therapeutic trials.1 However, can one speak of placebo-controlled trials when the patient is told that he or she might receive an inactive drug or procedure? A placebo is defined in the Shorter Oxford Dictionary of 1811 as “a medicine given more to please than to benefit the patient.”2 Thus a placebo is a pharmacologically inert drug or a dummy procedure prescribed with therapeutic intent. Patients in modern-day clinical therapeutic trials are, by this definition, not given a placebo and cannot be under current guidelines.

The prescribing of a placebo implies deception. Conversely, allocating an inert therapy to a patient who has been instructed that it is inert, with their consent, is quite a different matter. Inert controls provide a greater delta of response than placebo controls.

Currently, the use of placebo therapy is denounced by most ethicists,3^,4 but practising physicians caring for patients find it more acceptable. Why is it deceitful to prescribe a placebo when most modern drugs, especially anti-rheumatic drugs, are only marginally better and certainly more toxic?5 Most alternative therapies can be considered super-placebos6 and are certainly very popular with patients. The greatest placebo is the doctor, a fact appreciated by William Osler.

I hope that the recent National Conference on Appropriate Placebo Use in Clinical Trials, held in Ottawa, was not only attended by scientists, ethicists and policy-makers, but also patients and their families. It is, after all, the patient who is at the end of the final common pathway.

W. Watson Buchanan Professor Emeritus McMaster University Hamilton, Ont.