What it's for (Indications)
- Valsartan is indicated for the treatment of hypertension (high blood pressure), heart failure, and post-myocardial infarction (heart attack), especially in cases with left ventricular failure or left ventricular diastolic dysfunction.
Dosage Information
| Type | Guideline |
|---|---|
| Standard | Dosage should be individualized based on patient tolerance and clinical response. Always consult your doctor for specific dosing instructions. * **Adult Hypertension**: Initial dose is 40 mg or 80 mg twice daily. The typical dose range is 40 mg to 160 mg twice daily. * **Pediatric Hypertension (age 6-16 years)**: Initial dose is 0.65 mg/kg twice daily (maximum initial dose of 40 mg total). The dose range is 0.65 mg/kg to 1.35 mg/kg twice daily (up to 40 mg-160 mg total). * **Heart Failure**: Initial dose is 40 mg twice daily. The dose range is 40 mg to 160 mg twice daily, with a target maintenance dose of 160 mg twice daily, as tolerated. * **Post-Myocardial Infarction**: Initial dose is 20 mg twice daily. The dose range is 20 mg to 160 mg twice daily, with a target maintenance dose of 160 mg twice daily, as tolerated. |
Safety & Warnings
Common Side Effects
- Most common adverse reactions observed in clinical studies include headache, dizziness, fatigue, and abdominal pain (in hypertension).
- For heart failure, common reactions include dizziness, hypotension, diarrhea, arthralgia, back pain, fatigue, and hyperkalemia.
- Following myocardial infarction, the most common adverse reactions leading to discontinuation are hypotension, cough, and increased blood creatinine.
- Rarely, patients may experience severe effects such as syncope (fainting), thrombocytopenia (low levels of platelets), renal (kidney) dysfunction, and angioedema (swelling under the skin or mucous membranes).
Serious Warnings
- Black Box Warning: WARNING: FETAL TOXICITY. When pregnancy is detected, discontinue Valsartan as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus.
- Caution is advised for patients with a history of hepatic (liver) impairment, severe renal (kidney) impairment, renal artery stenosis (narrowing of renal arteries), severe cardiac insufficiency, aortic or mitral stenosis (narrowing of heart valves), and angioedema.
- Potassium levels should be monitored, particularly in elderly patients.
- This medicine should not be used by lactating mothers; consultation with a doctor is recommended.
- Patients should avoid driving or operating machinery as this medication may impair their ability to do so.
- Alcohol consumption should be avoided while taking Valsartan.
- Note that Valsartan Oral Solution is not therapeutically equivalent to the tablet formulation, and its peak concentration is higher.
How it Works (Mechanism of Action)
Valsartan selectively blocks the binding of angiotensin II to the AT1 receptor, located in various tissues such as vascular smooth muscle and the adrenal gland. This action counteracts the vasoconstrictor and aldosterone-secreting effects of angiotensin II, which is the primary pressor agent of the renin-angiotensin system. Its mechanism of action is independent of the pathways involved in angiotensin II synthesis. Valsartan exhibits a significantly higher affinity (approximately 20,000-fold) for the AT1 receptor compared to the AT2 receptor, which is not primarily associated with cardiovascular homeostasis.