Nifedipine is a calcium-antagonist whose principal action is reduction of peripheral resistance. The utilization of nifedipine is still limited in infancy. We have studied the immediate effect on hypertensive blood pressure values of nifedipine administered sublingually in 10 children (3 males and 7 females; aged 6-14 years) with different clinical diagnoses: acute glomerulonephritis (6 cases), lupus erythematosus systemicus (2 cases), membrane proliferative glomerulonephritis (1 case), pyelonephritis secondary to vesico-ureteral reflux (1 case). Nifedipine (0.25-0.50 mg/Kg) lowered systolic and diastolic blood pressure values from 167.5 +/- 19.8 mmHg and 103.5 +/- 18.4 mmHg to 126 +/- 19.8 mmHg and 81.5 +/- 15.1 mmHg, respectively, 30 minutes after administration (p less than 0.001). We propose nifedipine as a simple, effective and safe alternative drug for managing hypertensive emergencies in childhood.