Hypnotic activity of placebo in relation to severity of insomnia: A quantitative evaluation

Data obtained in a controlled clinical trial, carried out on 78 psychiatric patients, are presented as a contribution to the quantitative evaluation of the relationship between the effects of placebo and drugs at a given dose and the severity of the clinical condition being treated. In these patients, suffering from insomnia of different severities, satiofactory sleep after administration of placebo was demonstrated to decrease significantly with increasing pretreatment severity of the symptom. Furthermore, the differences in hypnotic activity between placebo and 100 mg. phenobarbital were almost nil in mild insomnia and increased significantly with increasing severity of insomnia. On the basis of these data, it is felt that some cases of mild insomnia may be better treated with placebo than with active drugs. Furthermore, clinical trials of hypnotic drugs appear to be more generally efficient if carried out with patients suffering from severe insomnia.