Nifedipine-induced fingertip vasodilation in patients with Raynaud's phenomenon.

The effect of nifedipine on fingertip hemodynamics was studied in 10 patients with Raynaud's phenomenon. Fingertip blood flow (FBF) was determined in a 20 degrees C environment by venous occlusion air plethysmography and fingertip vascular resistance (FVR) was calculated from the mean blood pressure and the FBF. Nifedipine, administered as a 10 mg sublingual dose, increased FBF in 8 of the 10 patients. FVR for the 10 patients decreased 40% from 40.7 +/- 10.8 to 24.2 +/- 6.1 U (p less than 0.05). Seven of the 10 patients were followed in a crossover placebo-controlled clinical trial. The frequency and severity of Raynaud's phenomenon was less in all seven patients when taking nifedipine as compared to placebo. Nifedipine-induced fingertip vasodilation may contribute to clinical improvement in some patients with Raynaud's phenomenon.