losartan

Losartan is metabolized in the liver to an active metabolite (which has a similar action to losartan). The time to peak effect after a dose is 1-2 hours for losartan and 3-4 hours for the metabolite. At its peak level, losartan inhibits 85% of the effects of angiotensin II, and 25 to 40% of this inhibition persists for 24 hours.