Evaluation of the Efficacy of Amlodipine vs Captopril/Hydrochlorothiazide in the Treatment of Essential Hypertension

The aim of this nonblinded randomised crossover study was to assess the efficacy of amlodipine 5 to 10 mg/day versus combination therapy with Captopril (50 to 100 mg/day) plus hydrochlorothiazide (25 to 50 mg/day) [CPT+HCTZ] over 12 weeks in patients with mild to moderate essential hypertension. Both treatment regimens were associated with statistically significant reductions in diastolic and systolic blood pressures from baseline, as determined by sphygmo-manometry. These findings were confirmed by ambulatory blood pressure monitoring, which showed that consistent reductions were maintained throughout the day, without the normal circadian rhythm being affected. Amlodipine produced slightly greater reductions in blood pressure, although this difference was not statistically significant. Early morning and evening blood pressures rose slightly when patients were switched from amlodipine to CPT+HCTZ, but fell with crossover to amlodipine. Both treatments were well tolerated, with a slightly lower incidence of adverse effects with the combination of CPT+HCTZ.