What is the recommended dosage of losartan (angiotensin II receptor antagonist) for treating hypertension?

Losartan Dosage for Hypertension

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

Initial Dosing

• For most adults with hypertension:

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

• For patients with possible intravascular depletion (e.g., on diuretic therapy):

  • Starting dose: 25 mg once daily 1

• For patients with hepatic impairment:

  • Starting dose: 25 mg once daily 1

Dose Titration

Losartan demonstrates dose-dependent blood pressure reduction. Clinical studies have shown:

• The 50-100 mg doses produce statistically significant systolic/diastolic mean decreases in blood pressure compared to placebo in the range of 5.5-10.5/3.5-7.5 mmHg 1
• If blood pressure is not controlled with the initial dose, increase to 100 mg once daily 1
• Doses above 100 mg daily do not provide additional antihypertensive effect for hypertension management 1

Special Populations

Elderly Patients

• No initial dosage adjustment is necessary for elderly patients 2
• Drug treatment can be initiated with angiotensin receptor antagonists like losartan in line with general guidelines 3
• Initial doses and subsequent dose titration should be more gradual in very old and frail subjects 3

Pediatric Patients

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

Patients with Renal Impairment

• No initial dosage adjustment is necessary for patients with renal insufficiency 2
• For patients with diabetic nephropathy, the usual starting dose is 50 mg once daily with titration to 100 mg once daily based on blood pressure response 1

Patients with Hepatic Impairment

• For mild-to-moderate hepatic impairment: 25 mg once daily
• Not studied in severe hepatic impairment 1

Administration Considerations

• Losartan can be administered without regard to food 2
• Taking medications at the most convenient time of day for the patient is recommended to establish a habitual pattern and improve adherence 3
• The pharmacokinetics of losartan are linear and dose-proportional 2

Combination Therapy

• For most patients with confirmed hypertension (BP ≥140/90 mmHg), combination BP-lowering treatment is recommended as initial therapy 3
• Preferred combinations include a RAS blocker (such as losartan) with a dihydropyridine calcium channel blocker or diuretic 3
• Fixed-dose single-pill combination treatment is recommended when using combination therapy 3
• Addition of a low dose of hydrochlorothiazide (12.5 mg) to losartan 50 mg once daily has shown enhanced blood pressure reduction 1

Monitoring

• Monitor blood pressure response to determine if dose adjustment is needed
• For patients switching from other antihypertensives to losartan, monitor blood pressure and renal function within 1-2 weeks after switching 4

Clinical Pearls

• Losartan is well tolerated with dizziness being the only drug-related event reported more frequently than placebo 5
• First-dose hypotension is uncommon 5
• Losartan has a favorable drug-drug interaction profile 2
• Losartan is contraindicated in pregnancy 4

By following these dosing recommendations, losartan can effectively control blood pressure while maintaining a favorable safety profile for patients with hypertension.