Increasing Losartan from 75 mg to 100 mg
Yes, increase the losartan dose to 100 mg once daily, as this is the guideline-recommended target dose for optimal cardiovascular protection and blood pressure control. 1
Rationale for Dose Escalation
The current regimen is suboptimal because:
- Losartan 100 mg once daily is the established target dose according to ACC/AHA guidelines, with 50 mg representing only 50% of the target dose 1
- The FDA-approved maximum dose is 100 mg daily, and clinical trials demonstrating cardiovascular benefits used this target dose 2
- At 75 mg, the patient is receiving 75% of the target dose, leaving room for further therapeutic benefit 1
Evidence Supporting 100 mg Dosing
Guideline recommendations strongly support maximizing ARB dosing:
- ACC/AHA performance measures specify that patients should receive at least 50% of target dose (50 mg for losartan), with 100 mg being the full target 1
- The LIFE study, which demonstrated cardiovascular benefits in hypertensive patients with left ventricular hypertrophy, titrated losartan to 100 mg daily 2
- Clinical pharmacology studies suggest that 50 mg may be insufficient, and 100 mg/day should be the preferred dose for maximal clinical efficacy 3
Dosing Strategy
The appropriate titration approach:
- Increase losartan from 75 mg to 100 mg once daily while continuing hydrochlorothiazide 25 mg 2
- The combination of losartan 100 mg plus HCTZ 12.5-25 mg produces additive blood pressure reductions of approximately 15.5/9.2 mmHg compared to baseline 2
- No dosage adjustment is needed based on age alone in this 65-year-old patient 2, 4
Monitoring Plan
After increasing to 100 mg:
- Reassess blood pressure within 2-4 weeks to evaluate response 5
- Target blood pressure is <130/80 mmHg for most patients 1, 5
- Monitor serum potassium and renal function, particularly when combining ARBs with diuretics 5
If Blood Pressure Remains Elevated
Should BP remain uncontrolled on losartan 100 mg plus HCTZ 25 mg:
- Add a calcium channel blocker (such as amlodipine) as the third agent before considering a fourth drug 5
- If still uncontrolled on three agents at optimal doses (resistant hypertension), add spironolactone 25 mg daily as the preferred fourth agent 5
- Verify medication adherence before adding additional agents 5
Important Considerations
Key safety points:
- Losartan is well-tolerated with dizziness being the only drug-related adverse effect more common than placebo 6, 7
- First-dose hypotension is uncommon with losartan due to its slower onset of action 6
- The drug does not require dosage adjustment for mild-to-moderate renal impairment 8
- Cough incidence with losartan is similar to placebo, making it advantageous over ACE inhibitors 7, 4