START OF THERAPY WITH THE ANGIOTENSIN-II ANTAGONIST LOSARTAN AFTER IMMEDIATE SWITCH FROM PRETREATMENT WITH AN ACE-INHIBITOR

Aims To evaluate initial blood pressure effects of the angiotensin II antagonist losartan (L) immediately after switching from an ACE inhibi tor (captopril, C). Methods Two-phase multicentre randomized study in 177 outpatients with mild to moderate essential hypertension. For 6 we eks all patients received 25 mg C twice daily. Then they were randomiz ed double-blind to switch for another 6 weeks to 50 mg L once daily (n =110) or to maintain C (n=55). On the first day of the switch they und erwent ambulatory blood pressure measurement (ABPM). Results Within 12 h of first dose, 31% of patients who switched to L had two consecutiv e systolic BP readings of 30 mmHg below their individual baseline valu e compared with 24% of patients who stayed on C. In 3% of, patients wi th L and in 6% of the C patients systolic BP readings less than 100 mm Hg were recorded within 12 h of first dose. The differences were not s tatistically significant. There were no clinical symptoms attributable to initial hypotension. During the 6 weeks double-blind therapy, 9% o f L patients experienced at least one adverse event, compared with 16% of patients with C. Conclusions In this study the angiotensin II anta gonist losartan was effective and generally well tolerated when admini stered immediately after pretreatment with an ACE inhibitor.