[A comparison and synergy in the treatment of essential arterial hypertension]

Forty patients with mild or moderate essential hypertension were studied. They received daily doses of either 240 mg verapamil or 10 mg enalapril, as well as a placebo. Total duration of trial was 24 weeks: a "washout" period of 2 weeks, a treatment period of 6 weeks with one of the two drugs, another "washout" period of 2 weeks, and another treatment period of 6 weeks with the alternate drug. Those patients with persistence of diastolic blood pressure (DBP) above 90 mmHg received simultaneously both drugs for an additional period of 8 weeks. Patients were assigned alternately to one of the groups. When each drug was given during the first treatment period, DBP was reduced below 90 mmHg in 15 of 19 patients receiving verapamil, and in 12 of 20 that received enalapril. When the drugs were given during the second treatment period, DBP became normal in 16 of 19 patients receiving enalapril, and in all the 18 patients treated with verapamil. Three patients achieved normal DBP when received simultaneously both drugs. Two patients withdrew from the trial for personal reasons and one for experimenting cough as reaction to enalapril. There were no other undesirable side effects. Laboratory tests did not show changes. Both products were similarly effective. Synergy was shown by the improvement of patients unresponsive to either drug when given singly, but responding when both were given simultaneously.