In a double blind placebo-controlled cross-over trial of 24 weeks 31 patients with Raynaud's syndrome were treated with the alpha-blocker phenoxybenzamine (10-20 mg daily) and with the combination of the alpha-blocker phenoxybenzamine (10-20 mg daily) and the beta-blocker sotalol (40-80 mg daily). A favourable effect on recovery of finger temperature after finger cooling was demonstrated after alpha-blockade as compared to the before treatment situation. This favourable effect was not different when the group received the combined alpha- and beta-blockade. The blood pressure was not influenced by either of the 2 medications. Fluid retention appeared with alpha-blockade and was absent with combined alpha- and beta-blockade. Decrease of heart rate occurred with alpha- plus beta-blockade and was absent with alpha-blockade alone. Clinical symptoms of Raynaud's syndrome equally were alleviated by the two medications. Common, and equally frequent side effects of the two medications were nasal congestion, disturbed ejaculation and potency, dry mouth, exercise-induced and orthostatic dizziness. We conclude that alpha-blockade is beneficial in Raynaud's syndrome and that additional beta-blockade counteracts the alpha-blocker side-effect fluid retention, reduces the heart rate and thus may prevent alpha-blocker induced tachycardia, and that it does not cause hypotension.