A double-blind clinical trial of mianserin versus amitriptyline: differentiation by adverse symptomatology.

A 6-week double-blind comparison of mianserin, a new antidepressant, and amitriptyline allowed us to explore the problem of demonstrating main effect differences in drug/drug trials when the focus is primarily only upon efficacy or upon common adverse symptomatology. Statistical analyses of standard psychiatric rating scales revealed no significant treatment differences, while both treatment groups exhibited significant parallel improvement across time. Examination of treatment emergent symptoms indicated that, while it evoked fewer anticholinergic symptoms than amitriptyline, mianserin exhibited a different profile of adverse symptomatology. The usefulness of a measure of the benefit/risk ratio was described as a means of clarifying drug/drug comparisons.