What is the appropriate dosing for Losartan (Angiotensin II receptor antagonist)?

From the Guidelines

Losartan should be initiated at a dose of 25-50 mg daily, with a goal dose of 25-100 mg daily in 1-2 divided doses, as this range has been shown to be effective in managing hypertension and reducing the risk of kidney disease progression 1.

Key Considerations

• The dose of Losartan may need to be adjusted based on blood pressure response, with a goal of achieving a blood pressure of less than 130/80 mm Hg.
• Patients with heart failure may require a lower starting dose of 25 mg daily, which can be gradually increased to 50-150 mg daily.
• Those with kidney disease or reduced kidney function should start with a dose of 25 mg daily.
• Elderly patients and those with liver impairment should also start with a dose of 25 mg daily.

Mechanism of Action and Monitoring

• Losartan works by blocking angiotensin II receptors, preventing blood vessel constriction and reducing blood pressure.
• Patients should be monitored for side effects like dizziness, hypotension, and elevated potassium levels.
• Blood pressure, kidney function, and potassium levels should be checked regularly, especially when starting treatment or adjusting doses.

Clinical Evidence

• A study published in the American Journal of Kidney Diseases in 2007 provides guidance on the dosing of ACE inhibitors and ARBs, including Losartan 1.
• Another study published in the European Heart Journal in 2012 provides evidence on the use of ARBs, including Losartan, in patients with heart failure 1.

Important Notes

• Losartan may take several weeks to reach its full therapeutic effect, so patience and consistent use are important for optimal results.
• The dose of Losartan should be adjusted based on individual patient response and clinical judgment.

From the FDA Drug Label

The usual starting dose of losartan is 50 mg once daily. The dosage can be increased to a maximum dose of 100 mg once daily as needed to control blood pressure [see CLINICAL STUDIES (14.1)]. A starting dose of 25 mg is recommended for patients with possible intravascular depletion (e.g., on diuretic therapy). Pediatric Hypertension The usual recommended starting dose is 0.7 mg per kg once daily (up to 50 mg total) administered as a tablet or a suspension [see DOSAGE AND ADMINISTRATION (2.5)]. Dosage should be adjusted according to blood pressure response. Doses above 1.4 mg per kg (or in excess of 100 mg) daily have not been studied in pediatric patients [see CLINICAL PHARMACOLOGY (12.3), CLINICAL STUDIES (14.1), and WARNINGS AND PRECAUTIONS (5.2)].

The appropriate dosing for Losartan is as follows:

• Adult Hypertension: 50 mg once daily, with a maximum dose of 100 mg once daily
• Pediatric Hypertension: 0.7 mg per kg once daily (up to 50 mg total)
• Patients with possible intravascular depletion: 25 mg once daily
• Patients with Hepatic Impairment: 25 mg once daily for mild-to-moderate hepatic impairment, with no recommendation for severe hepatic impairment 2

From the Research

Dosing of Losartan

• The optimal dose of losartan for renoprotection and blood pressure reduction in type 1 diabetic patients with diabetic nephropathy is 100 mg daily 3.
• Losartan 100 mg daily was significantly more effective than 50 mg daily in reducing albuminuria and blood pressure in type 1 diabetic patients with diabetic nephropathy 3.
• In type 2 diabetic patients with nephropathy, losartan 50 to 100 mg once daily reduced the incidence of doubling of serum creatinine, end-stage renal disease, and death 4, 5.
• The maximum losartan dose used in the RENAAL and LIFE studies was 100 mg daily, and it was effective in reducing the primary composite endpoint and the incidence of end-stage renal disease 6.
• Losartan 50 to 100 mg daily was also effective in reducing blood pressure in hypertensive patients with chronic renal insufficiency, including those with mild, moderate to severe, or end-stage renal disease 7.

Dosage Adjustments

• The dose of losartan may need to be adjusted based on the patient's response to treatment and their renal function 3, 7.
• In patients with chronic renal insufficiency, the dose of losartan may need to be increased to 100 mg daily to achieve adequate blood pressure control 7.
• Losartan can be used in combination with other antihypertensive medications, excluding angiotensin-converting enzyme inhibitors and other angiotensin receptor blockers, to achieve blood pressure targets 6.