Converting Lisinopril 40mg to Olmesartan
Start olmesartan at 20 mg once daily when converting from lisinopril 40 mg daily, then titrate to 40 mg once daily after 2 weeks if blood pressure control is inadequate. 1, 2
Rationale for Starting Dose
- Lisinopril 40 mg represents the maximum recommended daily dose for hypertension, placing the patient at the upper end of ACE inhibitor therapy 1
- Olmesartan 20 mg once daily is the recommended starting dose for most patients according to FDA labeling and ACC/AHA guidelines 1, 2
- The olmesartan dose range is 20-40 mg daily, with 40 mg being the maximum approved dose that provides optimal blood pressure reduction 1, 2
Titration Strategy
- After 2 weeks on olmesartan 20 mg daily, increase to 40 mg once daily if blood pressure remains uncontrolled (≥130/80 mmHg for most adults) 2, 3
- Olmesartan demonstrates dose-dependent efficacy, with the 40 mg dose producing significantly greater blood pressure reductions (approximately 12/7 mmHg from baseline) compared to 20 mg (approximately 10/6 mmHg) 2, 4
- Doses above 40 mg do not provide additional benefit, and twice-daily dosing offers no advantage over once-daily administration 2
Clinical Considerations During Conversion
- Monitor blood pressure within 1-2 weeks after switching to assess adequacy of initial olmesartan dose 5
- Check serum creatinine and potassium within 1-2 weeks after conversion, as both ACE inhibitors and ARBs carry risk of hyperkalemia and renal dysfunction 1, 5
- Ensure adequate washout if patient has history of angioedema with ACE inhibitors - wait at least 6 weeks after discontinuing lisinopril before starting olmesartan 1
- Consider starting at a lower dose (10-20 mg) in volume-depleted patients or those on concurrent diuretic therapy 2
Expected Outcomes
- Onset of antihypertensive effect occurs within 1 week, with maximal effect by 2 weeks 2, 6
- At 40 mg daily, olmesartan provides 24-hour blood pressure control with trough-to-peak ratios of 60-80% 2
- Olmesartan 40 mg has demonstrated superior or equivalent efficacy compared to other ARBs and ACE inhibitors in comparative trials 6, 7
Common Pitfalls to Avoid
- Never combine olmesartan with ACE inhibitors - this increases risk of hyperkalemia, syncope, and acute kidney injury without additional benefit 1, 5
- Do not start at 40 mg in most patients - the FDA-approved starting dose is 20 mg, with titration based on response 2
- Avoid abrupt discontinuation of lisinopril - transition directly to olmesartan on the same day to maintain continuous renin-angiotensin system blockade 1
- Do not exceed 40 mg daily of olmesartan - higher doses provide no additional efficacy 2