Losartan

Angiotensin II Receptor Blocker (ARB)

Drug Class: Angiotensin II Receptor Blocker (ARB)
Mechanism of Action (MOA): Blocks angiotensin II at the AT1 receptor → vasodilation, ↓ aldosterone (no effect on bradykinin).
Black Box Warning: Fetal toxicity — discontinue as soon as pregnancy is detected.
Clinical Notes: ARB of choice when ACE inhibitors cause cough; far less angioedema. Watch K⁺ and creatinine.
Source: FDA label