An oral calcium antagonist for treatment of hypertensive emergencies.

The efficacy and safety of 20 mg of nifedipine as a single oral dose have been studied with respect to the use of the drug as an alternative treatment of hypertensive emergencies. The study population consisted of nine male and nine female patients, 47 to 80 years old. The mean systolic blood pressure decreased from 220 +/- 22 to 150 +/- 21 mm Hg and the mean diastolic blood pressure from 122 +/- 11 to 86 +/- 10 mm Hg (p less than 0.001) within 20-30 min. The decrease of blood pressure was paralleled by a small but significant increase (p less than 0.01) in heart rate from 74 +/- 9 to 85 +/- 10 beats/min. The fall of blood pressure was directly related to pretreatment values. Oral nifedipine can be recommended as a first-line drug to lower blood pressure in hypertensive emergencies.