What is the recommended dose of losartan (angiotensin II receptor antagonist) for treating hypertension and diabetic nephropathy?

Losartan Dosing for Hypertension and Diabetic Nephropathy

For hypertension, start losartan at 50 mg once daily and titrate to 100 mg once daily as needed for blood pressure control; for diabetic nephropathy, start at 50 mg once daily and increase to 100 mg once daily based on blood pressure response. 1

Standard Dosing for Hypertension

• The FDA-approved starting dose is 50 mg once daily, with a maximum dose of 100 mg once daily 1
• Dosing can be administered without regard to food 2
• For patients with possible intravascular depletion (e.g., those on diuretic therapy), start with 25 mg once daily 1
• Blood pressure reduction is dose-dependent, with 50 mg producing near-maximum effects and 100 mg providing additional benefit in some patients 3
• The American College of Cardiology recommends titrating up to 100 mg once daily as needed to achieve blood pressure control 4, 5

Dosing for Diabetic Nephropathy

• Start at 50 mg once daily and increase to 100 mg once daily based on blood pressure response 1
• The 100 mg daily dose is optimal for renoprotection, reducing albuminuria by 48% compared to 30% with 50 mg daily 6
• Higher doses (100 mg) are significantly more effective than 50 mg in reducing both albuminuria and blood pressure without additional benefit from 150 mg 6
• The RENAAL trial demonstrated that losartan 50-100 mg daily reduced the risk of doubling serum creatinine by 25% and end-stage renal disease by 28% in type 2 diabetic patients with nephropathy 7
• KDIGO guidelines support losartan dosing of 25-100 mg daily in 1-2 divided doses for diabetic kidney disease, not exceeding 100 mg 4

Titration Strategy

• Adjust therapy no more frequently than every 2 weeks to target doses or maximally tolerated doses 4
• Monthly follow-up is recommended after initiation or dose adjustment until blood pressure control is achieved 5
• Monitor renal function and serum potassium within 1-2 weeks after initiating treatment, especially in patients with systolic blood pressure <80 mmHg or serum creatinine >3 mg/dL 4

Special Populations

Hepatic Impairment

• In patients with mild-to-moderate hepatic impairment, start with 25 mg once daily 1
• Losartan has not been studied in severe hepatic impairment 1

Renal Impairment

• No dosage adjustment is necessary for various degrees of renal insufficiency 2
• Losartan is recommended for chronic kidney disease with eGFR >30 mL/min per 1.73 m² 8
• Regular monitoring of electrolyte balance and serum creatinine is recommended 8

Pediatric Patients

• Starting dose is 0.7 mg/kg once daily (up to 50 mg total) for children ≥6 years 1
• Maximum dose is 1.4 mg/kg daily (not to exceed 100 mg) 1
• Not recommended in children <6 years or with eGFR <30 mL/min/1.73 m² 1

Combination Therapy Considerations

• If blood pressure remains uncontrolled on losartan 100 mg daily, add hydrochlorothiazide 12.5-25 mg daily 1
• Avoid combining losartan with ACE inhibitors, as this increases the risk of hyperkalemia and renal dysfunction 4, 5
• The combination of losartan with ACE inhibitors and aldosterone antagonists is potentially harmful and should be avoided 4

Common Pitfalls

• Underdosing is widespread in clinical practice, with less than 25% of patients titrated to target doses 4
• Physicians often hesitate to uptitrate due to concerns about hypotension, but the most dramatic blood pressure decreases occur with the initial dose rather than subsequent increases 5
• The maximum FDA-approved dose for hypertension is 100 mg once daily, though some heart failure guidelines reference higher doses (150 mg) used in specific trials 4, 1