Drug surveillance in general practice: a study of oxprenolol in the treatment of angina.

Information on the incidence of adverse drug reactions is essential for rational drug therapy. Accurate information of this type is almost entirely derived from intensive surveillance of hospital patients and may not reflect the situation in general practice. In a sutdy of oxprenolol (Trasicor) in the treatment of angina in general practice, a simple non-comparative assessment of efficacy indicated complete or substantial relief of symptoms in nearly 80 percent of patients. Side effects, which were principally related to beta-blockade and were all reversible, occured in 16.6 percent of patients but necessitated stopping treatment in only 10 percent. Simple studies of this nature may yeild valuable evicence about the benefit-to-risk ratio of drugs used under general practice conditions.