Angiotensin receptor antagonists, angiotensin receptor blockers (ARBs), or simply sartans are used to treat hypertension, heart failure, and diabetic nephropathy (kidney disease in diabetes). These drugs work by antagonising the effect of the enzyme angiotensin II, which leads to blood pressure reduction. They are an alternative to ACE inhibitors. ACE-I are usually used as a first-line medication, but some patients develop a troublesome dry cough with ACE-I and then ARBs are an excellent alternative.

Candesartan, eprosartan, irbesartan, losartan, valsartan and telmisartan are some examples of ARBs. Angiotensin receptor antagonists usually are well tolerated but, like any other medication, may have side effects. Particularly important is to monitor kidney function; a blood sample will be usually taken 7-10 days after starting ARBs and then always following a change in dose.