In this episode, we review the pharmacology, indications, adverse effects, monitoring, and unique drug characteristics of angiotensin receptor blockers (ARBs).
Key Concepts
- ARBs are equally efficacious as ACE inhibitors when used for hypertension, heart failure with reduced ejection fraction (HFrEF), chronic kidney disease (CKD) with proteinuria, and post-MI care. Some limited evidence suggests that they might be better in reducing albuminuria in patients with diabetes. ARBs are generally better tolerated than ACEi due to a lower risk of angioedema and dry cough.
- While most ARBs are comparable to each other, small differences exists regarding hepatic metabolism (CYP metabolism for losartan, telmisartan, and azilsartan), degree of blood pressure lowering (generally better with azilsartan, olmesartan, valsartan, and candesartan), and additional pharmacological effects (telmisartan with PPAR-Y agonism, losartan with uricosuric effect).
- ARBs are contraindicated in pregnancy, those with bilateral renal artery stenosis, and those with previous angioedema to ARBs. The most common adverse effects include hypotension and hyperkalemia, but in rare cases acute renal impairment can also occur.
- Baseline serum creatinine and potassium should be monitored in patients taking ARBs. After initiation or dose adjustment, blood pressure, serum creatinine, and potassium should be repeated in 1-2 weeks. Signs and symptoms of hypotension as well as angioedema should be monitored throughout the treatment period.