Prozart Mechanism of Action

Pharmacology: Pharmacokinetics: Losartan is readily absorbed from the gastrointestinal tract, but undergoes substantial first-pass metabolized resulting in a systemic bioavailability of about 33%. It is metabolized to an active carboxylic acid metabolized which has greater pharmacological activity then losartan; some inactive metabolites are also formed, Metabolism is primarily by cytochrome P450 isoenzymes CYP2C9 and CYP3A4. Peak plasma concentrations of losartan and E-3174 occur about 1 hour and 3 to 4 hours, respectively, after an oral dose. Both losartan and E-3174 are more than 98% bound to plasma proteins. Losartan is excreted in the urine and in the faeces via bile, as unchanged drug and metabolites. Following oral dosing about 4% of the dose is excreted in urine as the active metabolite. The terminal elimination half-lives of losartan and E-3174 are about 1.5 to 2.5 hours and 3 to 9 hours, respectively.