Class: Angiotensin II receptor antagonist
- Tablets 40 mg
- Tablets 80 mg
- Tablets 160 mg
- Tablets 320 mg
Antagonizes the effect of angiotensin II (vasoconstriction and aldosterone secretion) by blocking the binding of angiotensin II to the AT 1 receptor in vascular smooth muscle and the adrenal gland, producing decreased BP.
T max is 2 to 4 h after dosing. Bioavailability is about 10% to 35%. Food decreases AUC about 40% and decreases C max about 50%.
Vd is about 17 L. Highly bound to albumin (about 95%).
The major metabolite, valeryl 4-hydroxy valsartan, accounts for about 9% of the dose.
Half-life is about 6 h. Valsartan is primarily recovered in the feces (about 83%) and urine (about 13%). Recovery is mainly unchanged drug, with only about 20% of the dose recovered as metabolite. The plasma Cl is about 2 L/h.
Special PopulationsRenal Function Impairment
No correlation between renal function and exposure to the drug.Hepatic Function Impairment
Patients with mild to moderate chronic liver disease have about twice the AUC value.Elderly
AUC is about 70% higher and t ½ is about 35% longer in elderly patients.
Indications and Usage
Treatment of hypertension; treatment of heart failure; reduction of CV mortality in clinically stable patients with left ventricular failure or dysfunction after MI.
Dosage and AdministrationHypertension
PO Initial dosage: 80 or 160 mg once daily. Maintenance dosage: 80 to 320 mg once daily.Children 6 to 16 yr of age
PO Initial dosage: 1.3 mg/kg (up to 40 mg) once daily. Adjust dose based on BP response. Dosages higher than 2.7 mg/kg (up to 160 mg) once daily have not been studied in children.Heart Failure
PO Initial dosage: 40 mg twice daily; titration to 80 and 160 mg twice daily should be done to the highest dose, as tolerated by the patient (max dose, 320 mg/day).Post-myocardial infarction
PO Initiate 12 h after MI at 20 mg twice daily. Titrate within 7 days to 40 mg twice daily with additional titrations to a target maintenance dosage of 160 mg twice daily, as tolerated by the patient.Hepatic/Renal Function Impairment
Exercise care with dosing in patients with hepatic or severe renal function impairment.
May be administered with or without food.
Store at 59° to 86°F in tightly closed container. Protect from moisture.
Drug InteractionsInhibitors of uptake transporters, such as organic anion-transporting polypeptide 1B1 (eg, cyclosporine, rifampin), and efflux transporters, such as multidrug resistant-associated protein (eg, ritonavir)
May increase valsartan plasma concentrations.Lithium
Plasma concentrations may be increased by valsartan, resulting in an increase in the pharmacologic and adverse reactions of lithium.Potassium-sparing diuretics (eg, spironolactone), potassium supplements
Coadministration may cause elevated serum potassium concentrations in certain high-risk patients.
Laboratory Test Interactions
None well documented.
Hypotension (7%); postural hypotension (2%); syncope (at least 1%).
Dizziness (17%); fatigue (3%); postural dizziness (2%); headache, vertigo (at least 1%).
Blurred vision (at least 1%).
Diarrhea (5%); abdominal pain (2%); nausea, upper abdominal pain (at least 1%).
Renal function impairment (at least 1%).
Elevated liver enzymes, hepatitis (postmarketing).
Arthralgia, back pain (3%); rhabdomyolysis (postmarketing).
Dry cough (3%).
Viral infection (3%); hypersensitivity (postmarketing).
When used in pregnancy, drugs that act directly on the renin-angiotensin system can cause injury and even death to the developing fetus. When pregnancy is detected, discontinue therapy as soon as possible.
Assess renal function in heart failure or post-MI patients.
Category D .
Safety and efficacy not established in children younger than 6 yr of age.Heart failure or post-MI patients
Use caution when initiating therapy; hypotension may occur.
Patients with renal artery stenosis may experience acute renal failure. Use caution in treating patients whose renal function may depend on the activity of renin-angiotensin-aldosterone system (eg, severe CHF).
Use with caution.
Symptomatic hypotension may occur after initiation of valsartan therapy in patients who are intravascularly volume depleted (eg, those treated with diuretics). Correct these conditions prior to administration of valsartan or start treatment under close medical supervision.
Bradycardia, hypotension, tachycardia.
- Instruct patient to take medication as prescribed at same time each day.
- Inform patients that valsartan controls but does not cure hypertension.
- Caution patients to take dose exactly as prescribed and not to stop taking medication even if feeling better. Instruct patient not to decrease or increase dosage.
- Instruct the patient in BP- and pulse-measuring skills. Advise patient to call health care provider if abnormal readings occur.
- Instruct patients in methods of fall prevention, including arising slowly and sitting on side of bed before standing, especially early in therapy.
- Inform patients of importance of adjunctive therapies such as dietary planning, a regular exercise program, weight reduction, a low-sodium diet, smoking cessation program, alcohol reduction, and stress management.
- Instruct patient to report the following symptoms to health care provider: changes in urinary output, discomfort during urination, dizziness, fatigue, jaundice, light-headedness, weakness.
- Emphasize importance of follow-up visits and frequent assessment of BP while taking drug.
- Instruct patients to avoid use of supplements or salt substitutes containing potassium without consulting health care provider first.
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