Angiotensin II Receptor Blockers (ARBs)

Summary

ARBs stands for Angiotensin II Receptor Blockers. The drug names of ARBs all end with “-sartan”, like losartan and valsartan. Clinically, ARBs lower blood pressure and are used to treat both hypertension and heart failure. Side effects of ARBs include increasing potassium levels, so you’ll want to monitor the patient’s potassium levels to monitor for hyperkalemia. ARBs are teratogenic and should not be taken during pregnancy. Other side effects include angioedema, dizziness, and hypotension. ARBs are contraindicated with renal artery stenosis. And remember, ARBs do not cause a cough which is why you may see patients switch over to ARBs from ACE inhibitors.

Key Points

• Angiotensin II Receptor Blockers (ARBs)
  • Key Drugs
    • “-sartan”
      • Losartan
      • Valsartan
  • Mechanism
    • Prevents angiotensin II from binding to the AT1 receptors, which are responsible for vasoconstriction and the release of aldosterone
    • Since ARBs block these receptors, the result is vasodilation and inhibition of sodium/water reabsorption at the kidney
  • Clinical Use
    • Hypertension
      • Used in patients who can’t tolerate ACE inhibitors
    • Heart failure
    • Diabetic nephropathy
  • Side Effects and Adverse Reactions
    • Teratogenic
      • Causes renal and cardiac defects or death of the fetus
      • Do not use during pregnancy
    • Hyperkalemia
      • Teach patient to avoid potassium supplements, potassium salt substitutes, and potassium-sparing diuretics
    • Hypotension
      • Closely monitor patient’s blood pressure
      • Instruct patient to get up slowly to avoid dizziness associated with orthostatic hypotension
    • Angioedema
      • Less common than with ACE inhibitors, but if it does occur it can be life-threatening
    • Dizziness (Orthostatic Hypotension)
      • Instruct patient to get up slowly to avoid dizziness associated with orthostatic hypotension
    • Contraindicated with renal artery stenosis
      • Using ARBs in patients with renal artery stenosis can lead to kidney failure
    • Do Not Cause Cough
      • ARBs are very similar to ACE Inhibitors, with a main difference being that ARBs do NOT cause a dry cough like ACE inhibitors do
      • Patients often switch over to ARBs from ACE inhibitors
    • Fatigue
    • Hypoglycemia