Sublingual Versus Oral Captopril for Decreasing Blood Pressure in Hypertension Urgency: A Randomized Clinical Trial

Background: Captopril, a short-acting antihypertensive agent, is widely used in case of emergency to control blood pressure. Although sublingual Captopril has a faster onset of action, it is less tolerated. Objectives: This study aimed to evaluate the efficacy, side effects, and tolerability of sublingual versus oral captopril in an emergency setting. Methods: Hypertensive patients, without acute target organ damage were randomly administered 25 mg Captopril sublingually or orally (35 patients in each group) using block randomization. Blood pressure was measured at 0, 10, 20, 30, 45, 60, and 120 minutes after the administration. Patient satisfaction was subjectively scored on a scale of 1 - 10, and any side effect was recorded (Iranian registered clinical trials # IRCT2015110924963N1). Results: The mean age of the study groups was 59.61 +/- 9.34 years. Systolic and mean blood pressure significantly decreased after 10, 20, and 30 minutes of sublingual administration (P < 0.05), but diastolic blood pressure did not decrease. This difference in the blood pressure reducing effect decreased by 60 and 90 minutes and almost equalized after 90 minutes. Headache was observed as a side effect in two patients in the sublingual group. The convenience and satisfaction scores were much lower in the sublingual group (median of 6 (25th percentile: 6, 75th percentile: 7) in sublingual group versus median of 10 (9, 10) in Captopril group, P < 0.001). Conclusions: In our study, the systolic and mean blood pressure decreased more rapidly in the sublingual Captopril group than in the oral Captopril group in the first 30 minutes after administration. Patients better tolerated the oral preparation, and the difference in the blood pressure reducing effect between the groups almost equalized after 90 minutes.