Overview
Valsartan is an angiotensin II receptor blocker (ARB) used primarily for the treatment of hypertension and heart failure. It works by selectively blocking the binding of angiotensin II to the AT1 receptor, leading to vasodilation and reduced aldosterone secretion. This results in decreased blood pressure and reduced cardiac workload.
Mechanism of Action
Valsartan is a selective angiotensin II receptor antagonist that blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor in vascular smooth muscle and the adrenal gland.
Indications
- Treatment of hypertension
- Heart failure (NYHA Class II-IV) to reduce cardiovascular mortality and hospitalization
- Post-myocardial infarction in clinically stable patients with left ventricular dysfunction or heart failure
Common Doses
- 40 mg
- 80 mg
- 160 mg
- 320 mg
Dosage
Hypertension: Initial dose 80-160 mg once daily, may increase to 320 mg daily. Heart failure: Initial dose 40 mg twice daily, titrated to 160 mg twice daily as tolerated. Post-MI: Start 20 mg twice daily, titrate to target of 160 mg twice daily.
Contraindications
- Known hypersensitivity to any component
- Coadministration of aliskiren with valsartan in patients with diabetes
Side Effects
- Dizziness
- Hypotension
- Hyperkalemia
- Headache
- Fatigue
- Upper respiratory infection
- Back pain
- Angioedema (rare but serious)
Interactions
- Potassium supplements/potassium-sparing diuretics (risk of hyperkalemia)
- NSAIDs (may reduce antihypertensive effect and worsen renal function)
- Lithium (increased lithium levels)
- Aliskiren (contraindicated in diabetic patients)
Counseling Points
- Take medication at the same time each day
- Report signs of angioedema (swelling of face, lips, throat) immediately
- Avoid potassium supplements unless prescribed by physician
- Monitor blood pressure regularly
- Report dizziness or lightheadedness, especially when standing up
- Use effective contraception during treatment