Starting Dose of Losartan for a 64-Year-Old Male with Gout and Hypertension
Start losartan at 50 mg once daily for this patient, as this is the standard FDA-approved starting dose for hypertension and provides both blood pressure control and uricosuric benefits for gout management. 1
Rationale for 50 mg Starting Dose
The FDA-approved labeling clearly states that the usual starting dose of losartan for adult hypertension is 50 mg once daily, with the option to increase to a maximum of 100 mg daily as needed for blood pressure control 1. This standard starting dose is particularly advantageous in patients with concurrent gout because:
- Losartan uniquely lowers serum uric acid levels among angiotensin II receptor blockers through its uricosuric properties, increasing urinary uric acid excretion by approximately 25% and reducing serum uric acid by 20-47 μmol/L 2
- The 50 mg once daily dose has been proven effective at decreasing serum uric acid levels from 538 ± 26 to 491 ± 20 μmol/L in hypertensive patients with hyperuricemia and gout 3
- EULAR guidelines specifically recommend losartan for hypertension management in gout patients due to its modest uricosuric effects 4, 5
Why Not Start Lower?
A 25 mg starting dose is only recommended for patients with possible intravascular depletion (e.g., those already on diuretic therapy) 1. Since this patient has gout, he should ideally not be on diuretics, making the standard 50 mg dose appropriate.
Titration Strategy
- Target dose is 100 mg once daily for optimal cardiovascular and urate-lowering benefits 4
- Titrate upward based on blood pressure response, as the dosage can be increased to a maximum of 100 mg once daily as needed 1
- Higher doses (100 mg) provide superior outcomes in heart failure trials (HEAAL study), though the uricosuric effect may not substantially increase beyond 50 mg daily 4, 3
Important Clinical Considerations
Monitor renal function and potassium levels as standard practice with ARB therapy, particularly given the patient's age and potential for chronic kidney disease 2
The uricosuric effect appears to decrease with time when a new steady state of lower serum uric acid is reached, so don't expect continuous reductions in uric acid beyond the initial treatment period 3
Losartan works by inhibiting URAT1 (urate transporter 1) in the renal tubules, which is the mechanism for its uricosuric action 6. This effect is independent of its blood pressure-lowering properties.
Common Pitfalls to Avoid
- Do not combine losartan with ACE inhibitors, as this combination is potentially harmful and not recommended for hypertension treatment 5
- Do not expect losartan 50 mg twice daily to provide greater uric acid lowering than 50 mg once daily—studies show no additional benefit from divided dosing, partly due to lower compliance with evening doses 3
- Do not use losartan as sole urate-lowering therapy in patients with severe tophaceous gout requiring aggressive urate lowering—it should be considered adjunctive to allopurinol or febuxostat in such cases 5
- Ensure any thiazide diuretics are discontinued when starting losartan, as the American College of Rheumatology conditionally recommends switching hydrochlorothiazide to alternative antihypertensives in gout patients 2