Effect of intravenous enalaprilat on severe essential hypertension

Objective To evaluate the acute antihypertensive effect and safety of intravenous administration of enalaprilat. Methods 172 patients with severe hypertension (DBP≥120 mm Hg, 118 male, 54 female, mean age 53±9 years old )were admitted to four hospitals which are in Shanghai, and Zhenjiang and Yangzhou in Jiangsu province. The study were divided into three groups: (1) Three different doses of enalaprilat (1.25mg, 2.5mg, 5mg)were injected by an intravenous bolus to 10 cases for each group to evaluate the appropriate dosage. (2) A comparison of enalaprilat (2.5mg iv )and phentolamin (5mg iv )in 54 for each group of severe hypertension. (3) The antihypertensive effect of continuous bolus injection of enalaprilat every 6 hours to 34 cases in 24 hours. Results (1) The bolus of 2.5 mg enalaprilat is the most appropriate dosage to decrease the severe hypertension. (2) After 1 24 hours,the blood pressure decreased significantly in both enalaprilat and phentolamin injection groups ( P 0.05), more reductions of systolic blood pressure and distolic blood pressure were seen in enalaprilat group than those in phentolamin group at 4, 6, 8 hours respectively ( P 0 05). (3) The antihypertensive effective rate was 96.3% in the group with bolus injection of 2.5mg enalaprilat, 100% in multitime (q6h) injection patients. (4)Slight adverse experiences of enalaprilat during the period of the study are dizziness(6/118), headache (2/118), numbness(4/118) and cough (5/118) included. Conclusion Intravenous enalaprilat(2.5 mg) can be used safely and effectively to control blood pressure in patients with severe hypertension.