Ketanserin and capillary flow in Raynaud's phenomenon.

The serotonin (S2) antagonist ketanserin has been proposed as a useful therapy for Raynaud's phenomenon. The present study was designed to investigate the effects of 8 weeks therapy with oral Ketanserin (40 mg tds for the last 6 weeks) on finger nailfold capillary flow velocity at rest and following cold challenge and symptom score in 30 patients with Raynaud's in a double-blind, placebo-controlled, parallel design study. The ketanserin treated group reported a 16.7% improvement in symptom score (p less than 0.05) relative to the end of the run-in phase compared with a 2.4% (NS) improvement in the placebo group. Improvement in capillary flow was confined to a significant (p less than 0.02) rise in rest flow in the ketanserin treated group but no beneficial changes were observed following cold challenge. The disparity between the subjective and objective benefits demonstrated for this drug suggest the possibility of a central action rather than one that involves the correction of a local vascular fault.