Lisinopril 10 mg to Losartan Conversion
For a patient taking lisinopril 10 mg daily, the equivalent dose of losartan is 50 mg once daily. 1
Dose Equivalence Table
The following conversion is recommended based on clinical guidelines: 1
| Lisinopril Dose | Losartan Equivalent |
|---|---|
| 2.5-5 mg | 25-50 mg |
| 10-20 mg | 50 mg |
| 20-40 mg | 100 mg |
Rationale for Conversion
The American Heart Association, American College of Cardiology, and Heart Failure Society of America guidelines establish that lisinopril 10-20 mg daily corresponds to losartan 50 mg daily as the standard starting equivalent dose. 1
While 50 mg is the appropriate initial conversion dose, the target dose of losartan for optimal cardiovascular outcomes is 100 mg daily, particularly in heart failure patients with reduced ejection fraction. 2, 1
Clinical trials demonstrate that higher doses of losartan (100-150 mg daily) provide superior cardiovascular outcomes compared to lower doses, similar to findings with lisinopril in the ATLAS trial. 1
Practical Conversion Strategy
Initial conversion approach: 1
- Start losartan at 50 mg once daily when converting from lisinopril 10 mg
- Monitor blood pressure, renal function, and potassium within 1-2 weeks after conversion 2
- Consider uptitration to 100 mg daily after 2 weeks if blood pressure control is inadequate and the medication is well-tolerated 2, 1
Titration schedule: 2
- Adjust therapy no more frequently than every 2 weeks
- Target the maximum tolerated dose, ideally 100 mg daily for heart failure or 100 mg daily for hypertension 2
Critical Safety Considerations
Never combine losartan with lisinopril or other ACE inhibitors, as this combination increases the risk of hyperkalemia and renal dysfunction without providing additional benefit. 2, 1
Monitor within 1-2 weeks after conversion: 2
- Serum creatinine/eGFR
- Serum potassium (especially in patients with chronic kidney disease, diabetes, or on potassium-sparing agents)
- Blood pressure in both sitting and standing positions
Contraindications: 2
- Pregnancy (discontinue immediately if pregnancy is detected)
- Combination with ACE inhibitors or direct renin inhibitors
Advantages of Losartan Over Lisinopril
Lower risk of angioedema and cough compared to ACE inhibitors, making losartan a suitable alternative for patients who experience these side effects with lisinopril. 1, 3
The incidence of cough with losartan is significantly lower than with lisinopril. 3
Common Pitfalls to Avoid
Underdosing is widespread in clinical practice, with less than 25% of patients ever titrated to target doses of 100 mg daily. 2 Don't stop at 50 mg if the patient can tolerate higher doses and requires better blood pressure control or has heart failure.
Don't assume 50 mg is the final dose - the HEAAL trial demonstrated that losartan 150 mg daily was superior to 50 mg daily, with a 10% relative risk reduction in death or heart failure hospitalization. 2, 1
Avoid premature discontinuation for mild hyperkalemia - implement potassium-lowering strategies (dietary modification, diuretic adjustment, potassium binders) before stopping the medication. 2