A Short and Longer Term Effect on Blood Pressure following Captopril Withdrawal

Abstract

The mechanism of the long-term blood pressure lowering effect of converting enzyme inhibition is uncertain.Nine patients (mean age 56; 5 male, 4 female; 7 white and 2 black) with previous severe essential hypertension who had been treated with captopril 25 mg t.d.5. and a diuretic for at least 6 months had their captopril stopped. The diuretic was continued throughout the study. Following the withdrawal of captopril patients were seen at 2, 12, 24, 48 and 72 hrs after the last dose of captopril until either their supine systolic blood pressure rose above 170 mmHg or their diastolic pressure above 104 mmHg at which time treatment with captopril was recommenced.At 12 hrs after withdrawal of captopril supine blood pressure had risen significantly compared to 2 hrs after the last dose (138/88?3.7/3.6-+ 157/99?5.6/3.6 mmHg (P<0.02)). This rise in blood pressure was associated with a rise in plasma angiotensin I1 from 12.1T2.0 to 19.2z3.7 pmol/L (P(0.005) and a fall in plasma renin activity from 6.722.2 to 4.2t1.3 ng/ml/hr (P <

Therapeutic Progress–review Xxix Is There a Role for Low-Dose Angiotensin Converting Enzyme Inhibitors in the Treatment of Mild to Moderate Hypertension?

“…However, when patients are followed up over a period of several weeks the maximal antihypertensive effect is not achieved until the patient has been on treatment for at least 4 weeks (40,41). Furthermore, once the drug is stopped the blood pressure returns to pre-treatment levels relatively slowly (42).…”