Captopril and hydrochlorothiazide in the fixed combination multicenter trial

Area of Science:

• Cardiology
• Pharmacology

Background:

• Severe side effects of captopril are often linked to high doses or patient vulnerability.
• A flat dose-response curve in high-dose captopril suggests potential for reduced efficacy or increased risk.

Purpose of the Study:

• To investigate the efficacy and safety of combining low-dose captopril with hydrochlorothiazide (HCTZ) for hypertension management.
• To explore an alternative therapeutic strategy for patients experiencing side effects or inadequate blood pressure control with captopril alone.

Main Methods:

• Two patient groups were studied: (a) 43 patients initiated on fixed-dose captopril 25 mg + HCTZ 25 mg twice daily, with dosage escalation to 50 mg + 25 mg if needed. (b) 12 patients switched from high-dose captopril (mean 325 mg/day) to low-dose captopril (mean 96 mg/day) in fixed combination with HCTZ.
• A 14-day washout period preceded combination therapy in group (a).

Main Results:

• In group (a), initial blood pressure of 189/106 mmHg decreased to 160/84 mmHg after 2 weeks and further to 146 mmHg systolic.
• Group (b) experienced a 70% dose reduction of captopril while on combination therapy.

Conclusions:

• Low-dose captopril combined with HCTZ offers an effective strategy for blood pressure reduction.
• This combination therapy may mitigate side effects associated with high-dose captopril, improving patient tolerability and treatment outcomes.