Raynaud's phenomenon caused by beta-receptor blocking drugs. Improvement after treatment with a combined alpha- and beta-blocker.

Twenty-four hypertensive patients reported vasospastic symptoms in their hands during treatment with beta-blocking drugs with different pharmacological properties. Twenty patients had symptoms when staying indoors and 11 did not always experience complete relief of symptoms following active rewarming attempts. Finger systolic blood pressures were measured after standardized local cooling. In 15 patients, blood pressure decreased to a pathological level during this procedure. Previous beta-blockade was changed to combined alpha- and beta-blockade with labetalol given twice daily in a mean dose of 259 mg/day for 3 months. After this period, most patients showed a decreased temperature sensitivity both objectively and subjectively. Blood pressure control was maintained at the previous level. Heart rate increased significantly during treatment with labetalol. Labetalol offers an alternative treatment to patients suffering from vasospastic side-effects of beta-blockers.