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[Individualising the evidence--single case randomized trial].

W E Haefeli
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Abstract

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.

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Adrenergic alpha-AntagonistsAntihypertensive AgentsBlood Pressure Monitoring, AmbulatoryDouble-Blind MethodErectile DysfunctionEvidence-Based MedicineHumansHypertensionMaleMiddle AgedNifedipinePain MeasurementRisk FactorsYohimbineCase ReportsEnglish AbstractJournal ArticleRandomized Controlled Trial

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W E Haefeli. 2006. [Individualising the evidence--single case randomized trial].. https://doi.org/10.1024/0040-5930.63.12.777

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