Nicardipine is the first dihydropyridine calcium channel blocker capable of intravenous administration. Seven pediatric patients with hypertensive emergencies attributable to various pathological processes were treated with intravenous nicardipine, starting at 1 microg/kg/min. Nicardipine appeared to be safe and effective in controlling hypertension in these patients. Two patients who received nicardipine through peripheral lines developed superficial thrombophlebitis. None of the five patients receiving nicardipine through a central line experienced phlebitis, and no other adverse effects were noted.