What is the recommended dose of Cozaar (losartan) for an adult patient with hypertension or diabetic nephropathy?

Recommended Dosing of Losartan (Cozaar) for Hypertension and Diabetic Nephropathy

For adult hypertension, start losartan at 50 mg once daily and increase to 100 mg once daily as needed to achieve blood pressure control; for diabetic nephropathy, start at 50 mg once daily and titrate 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 This dosing applies to most adult patients with essential hypertension.

Special Considerations for Initial Dosing

• Patients with possible intravascular volume depletion (such as those on diuretic therapy) should start at 25 mg once daily to avoid first-dose hypotension 1
• Patients with mild-to-moderate hepatic impairment should also begin with 25 mg once daily 1
• The medication can be taken without regard to food 2

Dosing for Diabetic Nephropathy

For type 2 diabetic patients with nephropathy, initiate losartan at 50 mg once daily and increase to 100 mg once daily based on blood pressure response. 1 This higher target dose is critical for renoprotection.

Evidence Supporting 100 mg Dosing for Nephropathy

• Research demonstrates that 100 mg daily is significantly more effective than 50 mg daily in reducing albuminuria (48% reduction vs 30% reduction) in type 1 diabetic patients with nephropathy 3
• The 100 mg dose provides superior blood pressure reduction compared to 50 mg without additional benefit from increasing to 150 mg 3
• ACE inhibitors or ARBs at maximum tolerated doses are recommended as first-line therapy for patients with diabetes and albuminuria (UACR ≥30 mg/g) 4

Dosing for Hypertension with Left Ventricular Hypertrophy

Start with 50 mg once daily, add hydrochlorothiazide 12.5 mg daily, then increase losartan to 100 mg once daily followed by increasing hydrochlorothiazide to 25 mg daily based on blood pressure response. 1 This stepped approach maximizes cardiovascular risk reduction in this high-risk population.

Pediatric Dosing (Ages 6 and Older)

• Start at 0.7 mg/kg once daily (maximum 50 mg total) 1
• Maximum dose is 1.4 mg/kg daily (not to exceed 100 mg) 1
• Losartan is not recommended in children under 6 years or with eGFR <30 mL/min/1.73 m² 1

Monitoring Requirements

When using losartan (or any ARB), monitor serum creatinine, eGFR, and potassium levels at least annually. 4 This is particularly important when:

• Combining with diuretics 4
• Using in patients with pre-existing renal impairment 4
• Titrating to higher doses 5

Key Monitoring Pitfalls

• Do not combine losartan with ACE inhibitors or other ARBs as this increases risk of hyperkalemia, syncope, and acute kidney injury without additional cardiovascular benefit 5
• In patients with declining renal function (eGFR <30 mL/min/1.73 m²), continuation of ARB therapy may provide cardiovascular benefit, but requires close monitoring 4

Clinical Context: Why 100 mg Matters

The 50 mg dose commonly prescribed may be suboptimal for many patients. 6 Evidence suggests:

• The active metabolite E3174 (10-40 times more potent than losartan) contributes substantially to antihypertensive effects 2
• Pharmacokinetic data support that 100 mg daily should be the preferred dose to maximize clinical efficacy 6
• The 100 mg dose is well-tolerated with adverse effects similar to placebo 7

Treatment Algorithm for Diabetes with Hypertension

1. For BP 130-139/80-89 mmHg: Lifestyle therapy for maximum 3 months, then add losartan if target not achieved 4
2. For BP ≥140/90 mmHg: Initiate losartan 50 mg immediately with lifestyle therapy 4
3. Titrate to 100 mg daily within 2-4 weeks if BP remains above target 1, 3
4. If albuminuria present (UACR ≥30 mg/g): Ensure dose reaches 100 mg for renoprotection 4, 3
5. If BP still not controlled on 100 mg: Add thiazide-like diuretic (chlorthalidone or indapamide preferred) or dihydropyridine calcium channel blocker 4

Safety Profile

• Losartan is contraindicated in pregnancy due to fetal harm 8, 1
• Cough incidence is similar to placebo, making it ideal for patients with ACE inhibitor-related cough 7
• First-dose hypotension is uncommon except in volume-depleted patients 7
• Adverse effects are minimal, with dizziness being the only event reported more frequently than placebo 7