Responses to nifedipine by patients with Raynaud's disease and Raynaud's phenomenon secondary to another disease.

Thirteen patients with Raynaud's phenomenon were studied; six patients had the primary disorder and in the other seven progressive systemic sclerosis was diagnosed. Each patient received 10 mg of nifedipine; telethermographic evaluation of the hands was performed in basal conditions and 30 minutes after the administration of the drug. A more marked increase of hand tissue temperature was observed in the patients with progressive systemic sclerosis than in those with the primary disorder.