A randomized, double-blind, placebo-controlled study of venlafaxine XR in out-patients with tension-type headache.

The aim of this study was to evaluate in a double-blind, randomized, placebo-controlled study the safety and efficacy of venlafaxine extended release (XR) in the prophylactic treatment of out-patients with tension-type headache (TTH) and no current depression or anxiety disorders. Sixty neurology and headache clinic out-patients meeting the International Headache Society diagnostic criteria for TTH were treated with venlafaxine XR (150 mg/day, n = 34) or placebo (n = 26) for 12 weeks. The primary efficacy variable was the decline in number of days with headache. At end-point, the venlafaxine XR group had a significantly greater decrease in the number of days with headache compared with placebo (P = 0.05). Differences with regard to secondary efficacy variables where not significant. The number needed to treat for responders (>or=50% reduction in days with headache) was 3.48. Six patients in the venlafaxine XR group interrupted therapy due to adverse events, while no patients in the placebo group did so for the same reason. The number needed to harm was 5.58. This study provides preliminary evidence for the efficacy and safety of venlafaxine XR 150 mg/day in reducing the number of days with TTH.