Alpha 2-agonist versus alpha 1-antagonist in mild-to-moderate hypertension: comparison of transdermal clonidine and terazosin monotherapies.

Author(s): Harris SI, Alvarez C

Affiliation(s): 330 S.W. 27th Ave. Suite 608, Miami, FL 33135, USA.

Publication date & source: 1997-01, Am J Ther., 4(1):9-15.

Publication type: Clinical Trial; Randomized Controlled Trial

A double-blind, double-dummy, parallel-group trial that used a predominantly Hispanic patient population with mild-to-moderate hypertension was designed to compare the efficacy, safety, and acceptability of monotherapy with either transdermal clonidine applied once a week or terazosin tablets taken once a day. Of 44 patients admitted, 20 of 22 in the transdermal clonidine group and 15 of 21 in the terazosin group (one patient was lost to follow-up) met the response criteria. These criteria included the completion of 1 full week of therapy with the smallest dose that resulted in a seated diastolic blood pressure of <90 mm Hg and the subsequent entrance into an 8-week maintenance therapy phase. At the end of the 8-week maintenance phase the mean seated diastolic blood pressure remained <90 mm Hg in the clonidine cohort but not in the terazosin cohort, yet the difference was not statistically significant. There was a significantly better response to clonidine when all patients who received treatment were considered. No adverse first-dose effects were experienced with terazosin. One patient who received transdermal clonidine developed contact dermatitis and withdrew from the study prematurely. The most common side effects associated with clonidine were dry mouth and fatigue while those associated with terazosin were headache and fatigue. Compliance was excellent in both groups. Seventy-nine percent of patients found transdermal clonidine preferable to the oral regimen.