[Individualising the evidence--single case randomized trial]

Author(s): Haefeli WE

Affiliation(s): Universitat Heidelberg.

Publication date & source: 2006-12, Ther Umsch., 63(12):777-81.

Publication type: Case Reports; English Abstract; Randomized Controlled Trial

A 64-year old patient with well controlled essential hypertension reported convincingly that oral yohimbine had beneficial acute effects in treating his erectile dysfunction. However, when asking for a prescription of the compound his physician was not very responsive because acute effects of this treatment are uncommon and a2-adrenoceptor antagonism was known to increase blood pressure. They decided to convince each other and to objectively document yohimbine's efficacy or failure using a single case randomized trial design, i.e. an experimental approach to perform a controlled study in a single individual and to collect data in a double-blind fashion. The results of 10 comparisons between placebo and oral yohimbine revealed no difference and prevented exposure of the patient with a potentially harmful drug combination.