Ritanserin in relapse prevention in abstinent alcoholics: Results from a placebo-controlled double-blind international multicenter trial

Ritanserin, a long-acting specific 5-HT2 receptor antagonist, revealed prom ising effects on alcohol intake behavior in both animal acid preliminary hu man studies. To test its effectiveness in alcohol dependence this phase III clinical trial was initiated, In a placebo-controlled, randomized, double- blind international multicenter study 493 patients with moderate or severe alcohol dependence (DSM-III-R) were treated with three doses of ritanserin 2.5 mg/day (n = 122), 5 mg/day (n = 123), 10 mg/day (n = 126), or placebo ( n = 122) over a period of 6 months. Ritanserin was well tolerated. The most frequent adverse experiences were headache and insomnia. A small increase in weight in the ritanserin-treated patients was observed. There were no si gnificant differences between any dose of ritanserin and placebo in the rel apse-rate, the time to relapse, craving for alcohol, or quantity and freque ncy of drinking after relapse. So far, neither ritanserin nor any other ser otonergic medication has shown its specific effectiveness in relapse preven tion in alcohol dependence.