What is the maximum recommended dose of Losartan (angiotensin II receptor antagonist)?

Maximum Recommended Dose of Losartan

The maximum recommended dose of losartan is 100 mg once daily for hypertension, hypertensive patients with left ventricular hypertrophy, and nephropathy in type 2 diabetic patients. 1

Dosing Guidelines for Different Indications

Hypertension

• The usual starting dose for adult hypertension is 50 mg once daily 1
• The dosage can be increased to a maximum of 100 mg once daily as needed to control blood pressure 1
• A lower starting dose of 25 mg is recommended for patients with possible intravascular depletion (e.g., those on diuretic therapy) 1
• According to the 2017 ACC/AHA guidelines, losartan's usual dose range is 50-100 mg per day, which can be administered in 1-2 daily frequencies 2

Hypertensive Patients with Left Ventricular Hypertrophy

• The usual starting dose is 50 mg of losartan once daily 1
• The dose can be increased to 100 mg once daily based on blood pressure response 1
• Hydrochlorothiazide may be added to the regimen as needed 1

Nephropathy in Type 2 Diabetic Patients

• The usual starting dose is 50 mg once daily 1
• The dose should be increased to 100 mg once daily based on blood pressure response 1
• Clinical evidence supports that 100 mg of losartan significantly reduced the albumin-to-creatinine ratio (ACR) and the risks of chronic kidney disease stage 5 and doubling of serum creatinine level compared with placebo 2

Special Populations and Considerations

Hepatic Impairment

• In patients with mild-to-moderate hepatic impairment, the recommended starting dose is 25 mg once daily 1
• Losartan has not been studied in patients with severe hepatic impairment 1

Renal Impairment

• No dosage adjustment is necessary for patients with various degrees of renal insufficiency 3
• Losartan is not removed during hemodialysis 3
• Losartan regimens (50-100 mg) were well tolerated in patients with chronic renal disease, including those on hemodialysis 4

Optimal Dosing for Specific Conditions

Diabetic Nephropathy

• For type 1 diabetic patients with diabetic nephropathy, studies suggest that 100 mg daily is the optimal dose for renoprotection and blood pressure reduction 5
• Losartan 100 mg daily was significantly more effective than 50 mg daily in reducing albuminuria (48% vs 30% reduction) 5
• Increasing the dose to 150 mg daily did not provide additional benefit over the 100 mg dose 5

Non-Diabetic Proteinuria

• For non-diabetic patients with nephrotic range proteinuria, 100 mg of losartan appears to be the optimal antiproteinuric dose 6
• The 50 mg dose was less effective, and the 150 mg dose did not provide additional antiproteinuric benefit 6

Clinical Pharmacology

• Losartan is rapidly absorbed after oral administration, reaching maximum concentrations in 1-2 hours 3
• Approximately 14% of a losartan dose is converted to the pharmacologically active E3174 metabolite, which is 10-40 times more potent than the parent compound 3
• The pharmacokinetics of losartan are linear and dose-proportional 3

Safety Considerations

• Losartan should be avoided during pregnancy, particularly in the second and third trimesters 3
• Do not use in combination with ACE inhibitors or direct renin inhibitors due to increased risk of hyperkalemia and renal dysfunction 7
• Monitor renal function and potassium levels, especially in patients with renal impairment 7

In conclusion, while losartan doses up to 150 mg have been studied in certain populations, the FDA-approved maximum dose and the dose supported by major clinical guidelines is 100 mg once daily for hypertension, left ventricular hypertrophy, and diabetic nephropathy.