What is the recommended dosing regimen for losartan (angiotensin II receptor antagonist)?

Losartan Dosing Recommendations

The recommended starting dose of losartan for adult hypertension is 50 mg once daily, with titration to a maximum dose of 100 mg once daily as needed for blood pressure control. 1

Adult Dosing by Indication

Hypertension

• Starting dose: 50 mg once daily 1
• Maximum dose: 100 mg once daily 1
• For patients with possible intravascular depletion (e.g., on diuretic therapy): Starting dose of 25 mg once daily 1
• For patients with mild-to-moderate hepatic impairment: Starting dose of 25 mg once daily 1

Hypertension with Left Ventricular Hypertrophy

• Starting dose: 50 mg once daily 1
• Titration: Increase to 100 mg once daily based on blood pressure response 1
• Consider adding hydrochlorothiazide 12.5 mg daily with potential increase to 25 mg daily 1

Nephropathy in Type 2 Diabetes

• Starting dose: 50 mg once daily 1
• Target dose: 100 mg once daily 1

Heart Failure

• Target dose: 150 mg once daily 2
• Starting dose: 50 mg once daily 2
• Evidence suggests higher doses (150 mg daily) provide better cardiovascular outcomes than lower doses 2
• The HEAAL trial demonstrated that 150 mg daily of losartan was superior to 50 mg daily, with a relative risk reduction of 10% in death or heart failure hospitalization 3

Pediatric Dosing for Hypertension

• Starting dose: 0.7 mg/kg once daily (up to 50 mg total) 1
• Maximum dose: 1.4 mg/kg once daily (not to exceed 100 mg daily) 1
• Not recommended for children under 6 years of age or with estimated GFR < 30 mL/min/1.73 m² 1

Dosing Considerations and Adjustments

Titration Schedule

• Adjust therapy no more frequently than every 2 weeks to target doses or maximally tolerated doses 2
• Losartan can be administered without regard to food 4

Special Populations

• No dosage adjustment necessary based on age, sex, or race 4
• No dosage adjustment necessary in patients with renal insufficiency 4
• Losartan is not removed during hemodialysis 4
• Contraindicated in pregnancy 4

Clinical Evidence Supporting Higher Doses

• For diabetic nephropathy, 100 mg daily was significantly more effective than 50 mg daily in reducing albuminuria (48% vs 30% reduction) without additional benefit at 150 mg 5
• For non-diabetic patients with nephrotic range proteinuria, 100 mg daily provided optimal antiproteinuric effect (-30%) compared to 50 mg (-13%) with no additional benefit at 150 mg 6
• Higher doses of losartan (100 mg) are recommended for optimal clinical efficacy in hypertension, heart failure, and renal diseases 7

Common Pitfalls and Caveats

• Avoid simultaneous use with ACE inhibitors due to increased risk of hyperkalemia and renal dysfunction 2
• Monitor for symptomatic hypotension in volume-depleted patients 1
• Losartan is metabolized primarily by CYP3A4, 2C9, and 2C10 isoenzymes, but has a favorable drug-drug interaction profile 4
• The 50 mg dose, while commonly prescribed, may be suboptimal for many patients, particularly those with heart failure or proteinuric kidney disease 7