Therapeutic efficacy of alpha-adrenoceptor blockade in primary and secondary Raynaud's syndrome.

Twenty patients with primary and 11 with secondary Raynaud's syndrome were treated with the alpha-adrenoceptor blocker phenoxybenzamine (10-20 mg daily). In the secondary group mean age and mean duration of symptoms as well as presence of positive ANA and positive Clq binding test were significantly higher than in the primary group. In both groups a beneficial effect of the medication on finger temperature 12 min after finger cooling and on clinical symptoms was established. Secondary Raynaud's syndrome reacted at least as well as primary syndrome.