Valsartan to Olmesartan Equivalent Dosing
For patients taking valsartan 320 mg daily (160 mg twice daily), the equivalent olmesartan dose is 40 mg once daily; for valsartan 160 mg daily, use olmesartan 20 mg once daily. 1
Guideline-Based Dose Equivalence
The ACC/AHA/HFSA heart failure guidelines establish that the target dose for valsartan is 160 mg twice daily (320 mg total daily), while olmesartan's typical maximum dose is 20-40 mg once daily. 1 Although olmesartan is not specifically listed in the heart failure medication tables (which include valsartan, candesartan, and losartan as the evidence-based ARBs), the hypertension guidelines provide dosing ranges showing olmesartan 20-40 mg daily as the therapeutic range. 1
Practical Conversion Approach
When switching from valsartan to olmesartan:
- Valsartan 320 mg daily → Olmesartan 40 mg once daily 1, 2
- Valsartan 160 mg daily → Olmesartan 20 mg once daily 1, 2
- Valsartan 80 mg daily → Olmesartan 10-20 mg once daily 1
Start olmesartan at the equivalent or slightly lower dose and titrate based on blood pressure response over 1-2 weeks. 2
Evidence Supporting Olmesartan Potency
Head-to-head trials demonstrate that olmesartan is more potent than other ARBs at standard doses. Olmesartan 20 mg was significantly more effective than valsartan 80 mg in reducing blood pressure in patients with essential hypertension. 3, 4 At week 8, olmesartan 40 mg once daily produced equivalent blood pressure reductions to valsartan 320 mg once daily. 3
In comparative studies, olmesartan 20 mg reduced seated diastolic blood pressure by 11.5 mm Hg compared to 7.9 mm Hg with valsartan 80 mg, demonstrating approximately 1.5-fold greater potency. 4 This supports the conversion ratio where olmesartan 20-40 mg approximates valsartan 160-320 mg. 3, 4
Important Clinical Considerations
For heart failure patients specifically: Valsartan has proven mortality benefit in heart failure trials with a target dose of 160 mg twice daily. 1 Olmesartan lacks this level of evidence in heart failure, so switching from valsartan to olmesartan in HFrEF patients is generally not recommended unless there is a compelling reason (such as intolerance). 1
Titration strategy: Olmesartan demonstrates dose-dependent efficacy, with 40 mg significantly more effective than 20 mg. 5 When uptitrating, increase the dose every 2-4 weeks based on blood pressure response and tolerability. 2, 5
Monitoring: Check blood pressure, renal function, and potassium levels within 1-2 weeks after switching, as with any ARB transition. 1