Pharmacokinetics and effects on renal function following cilazapril and hydrochlorothiazide alone and in combination in healthy subjects and hypertensive patients.

1. Possible interactions between cilazapril and hydrochlorothiazide with respect to pharmacokinetics and renal effects were investigated in healthy subjects (single dose) and in hypertensive patients (multiple dosing). 2. No significant pharmacokinetic interaction was found between cilazapril and hydrochlorothiazide. 3. Cilazapril showed weak saluretic properties as compared with hydrochlorothiazide, but increased the saluretic effects of hydrochlorothiazide. 4. Cilazapril attenuated the hypokalaemia observed with hydrochlorothiazide in hypertensive patients. 5. The effect on blood pressure reduction obtained from the combination of cilazapril and hydrochlorothiazide lasted longer than that of cilazapril alone.