Intravenous nicardipine in Raynaud's phenomenon: a controlled trial.

The hemodynamic effects of intravenously administered nicardipine (5 mg/h during 85 min) were investigated in 12 Raynaud patients and in 12 healthy volunteers in a double-blind placebo-controlled cross-over study. In both groups we found no change in systolic blood pressure, but a significant fall in diastolic blood pressure of 7 mm Hg (p less than 0.001). Heart rate increased 14 beats/min (p less than 0.001) and forearm blood flow increased 1.0 ml/100 ml/min (p less than 0.01) with a concomitant decrease of 10 arbitrary units (AU) in forearm vascular resistance (p less than 0.001). In healthy volunteers the recovery of the finger skin temperature after cold challenge improved significantly (p less than 0.05). In patients with primary Raynaud's phenomenon we observed a significant (p less than 0.001) increase in skin temperature of 4.6 degrees C before cooling, together with a better recovery after cold induced vasospasm (p less than 0.001). In secondary Raynaud's patients, nicardipine caused no vasodilatation within the skin vessels. There were no significant correlations between the plasma nicardipine concentration and any of the observed pharmacological effects.