Cold-induced Raynaud's phenomenon ameliorated by intravenous administration of ketanserin: a double-blind cross-over study.

Fifteen patients suffering from Raynaud's phenomenon (RP) were examined. They were placed in a "climate chamber" (a small room in which the temperature and humidity could be varied). The temperature was gradually decreased, while the humidity was kept constant. After 60-90 min, distinct RP was induced and intravenous medication was administered. The whole trial was performed in a double-blind, cross-over fashion. Every patient participated in two experiments performed 2 days apart. Either ketanserin or placebo was given during the first experiment. In the second experiment, the medication (or placebo) which had not been given was administered. The effects of ketanserin were highly significant: the bluish pallor changed into bright erythema and the skin temperature rose significantly. This was interpreted as a spasmolytic effect. Intravenously administered ketanserin has a place in the clinical treatment of acutely deteriorating RP of diverse etiologies.