Recommended Dosing of Losartan for Hypertension
The recommended starting dose of losartan for adult hypertension is 50 mg once daily, with the option to increase to a maximum dose of 100 mg once daily as needed to control blood pressure. 1
Initial Dosing and Titration
- The FDA-approved starting dose for losartan in adult hypertension is 50 mg once daily 1
- A lower starting dose of 25 mg is recommended for patients with possible intravascular depletion (e.g., those on diuretic therapy) 1
- Dosage can be titrated up to a maximum of 100 mg once daily based on blood pressure response 1
- Clinical trials have demonstrated that losartan doses of 50-100 mg once daily produce statistically significant systolic/diastolic mean decreases in blood pressure compared to placebo 1
Special Populations
- For patients with mild-to-moderate hepatic impairment, the recommended starting dose is reduced to 25 mg once daily 1
- Losartan has not been studied in patients with severe hepatic impairment 1
- No dosage adjustment is necessary for patients with various degrees of renal insufficiency 2
- For pediatric hypertension (ages 6-16 years), the usual recommended starting dose is 0.7 mg/kg once daily (up to 50 mg total) 1
Dosing Schedule
- Losartan can be administered once daily without regard to food 2
- Peak effects occur at 6 hours after dosing, with trough-to-peak ratio for systolic and diastolic responses of 50-95% and 60-90%, respectively 1
- The pharmacokinetics of losartan are linear and dose-proportional, with no substantial changes with repetitive administration 2
Efficacy Considerations
- Higher doses (100 mg daily) provide better cardiovascular outcomes than lower doses, particularly in patients with heart failure or left ventricular hypertrophy 3
- The addition of hydrochlorothiazide 12.5 mg to losartan 50 mg once daily results in enhanced blood pressure reduction 1
- Losartan is effective in reducing blood pressure regardless of race, although the effect may be somewhat less in Black patients 1
Common Pitfalls to Avoid
- Avoid simultaneous use of ACE inhibitors and losartan, as this combination increases the risk of hyperkalemia and renal dysfunction 4, 3
- Ensure adequate blood pressure monitoring during dose titration, especially when starting with the lower 25 mg dose in volume-depleted patients 1
- Losartan should be avoided during pregnancy, particularly in the second and third trimesters, as it is associated with serious fetal toxicity 2
Comparative Efficacy
- Losartan 50-100 mg once daily has been shown to lower blood pressure to a similar degree as enalapril, atenolol, and felodipine extended release 5
- Losartan has a favorable tolerability profile with dizziness being the only drug-related event reported more frequently than placebo 5, 6
By following these dosing recommendations, clinicians can effectively manage hypertension while minimizing adverse effects and optimizing cardiovascular outcomes.