Starting Dose of Losartan for Hypertension
The usual starting dose of losartan for adult hypertension is 50 mg once daily, which can be increased to a maximum dose of 100 mg once daily as needed to control blood pressure. 1
Standard Dosing Recommendations
- The FDA-approved starting dose for losartan in adult hypertension is 50 mg once daily, with titration up to 100 mg once daily based on blood pressure response 1
- A lower starting dose of 25 mg once daily is recommended for patients with possible intravascular depletion (e.g., those on diuretic therapy) 1
- For patients with mild-to-moderate hepatic impairment, the recommended starting dose is reduced to 25 mg once daily 1
Pharmacokinetic Considerations
- Losartan is rapidly absorbed after oral administration, reaching maximum concentrations within 1-2 hours 2
- Approximately 14% of losartan is converted to its active metabolite E-3174, which is 10-40 times more potent than the parent compound 2
- The long half-life (6-9 hours) of the active metabolite E-3174 contributes to losartan's effectiveness as a once-daily medication 2
- Losartan can be administered without regard to food 2
Special Populations
- No dosage adjustment is necessary for elderly patients or based on gender or race 2
- No dosage adjustment is needed for patients with various degrees of renal insufficiency 2, 3
- Losartan has not been studied in patients with severe hepatic impairment 1
Clinical Efficacy and Tolerability
- Losartan effectively reduces blood pressure at the standard starting dose of 50 mg, with most patients maintained on this dose 4
- The 50 mg dose is well-tolerated, with dizziness being the most commonly reported drug-related adverse effect 5
- The overall rate of withdrawal due to adverse effects is low (2.3%), which is actually lower than placebo (3.7%) in clinical trials 5
- First-dose hypotension is uncommon with losartan, possibly due to its slower onset of action compared to some other antihypertensives 5
Dose Titration
- If blood pressure is not adequately controlled with the 50 mg starting dose, the dose can be increased to 100 mg once daily 1
- For hypertensive patients with left ventricular hypertrophy, the recommended approach is to start with 50 mg once daily, then add hydrochlorothiazide 12.5 mg and/or increase losartan to 100 mg once daily based on blood pressure response 1
- For patients with nephropathy in type 2 diabetes, the starting dose is also 50 mg once daily, with titration to 100 mg once daily based on blood pressure response 1
Practical Considerations
- The American College of Cardiology recommends losartan be administered once daily at a target dose of 100 mg for optimal clinical outcomes 6
- Higher total daily doses of losartan (150 mg daily) have been shown to be superior to lower doses (50 mg daily) in reducing heart failure hospitalizations 6
- Clinicians often underdose angiotensin receptor blockers in clinical practice, failing to reach target doses proven to reduce morbidity and mortality 6