Incidence of side effects during the application of placebo and active therapy (Tobanum) in patients suffering from hypertension, angina pectoris and arrhythmia.

In a single blind clinical trial the effects of Tobanum (chloranolol), a beta-adrenergic receptor blocker, on 450 patients were examined. The side effects were detected by placebo control. Complaints were recorded on a questionnaire in the placebo period as well as in the active treatment period. Every fourth patient reported complaints in the placebo period and every third had a new complaint in the active period. Qualitative and quantitative analysis of the complaints indicated that Tobanum has mainly cardiorespiratory side effects judging from the beta-blocker characteristics. The study draws attention to the need for awareness of complaints in the placebo period for correct evaluation of side effects.