From the Guidelines
Olmesartan is generally considered more potent and longer-acting than losartan for treating hypertension, with a typical starting dose of 20 mg once daily, which can be increased to 40 mg if needed, as recommended by the 2020 ACC/AHA clinical performance and quality measures for adults with heart failure 1.
Comparison of Losartan and Olmesartan
- Both medications are angiotensin II receptor antagonists, used to treat hypertension and protect the kidneys from damage due to diabetes or other conditions.
- Olmesartan has a longer half-life, providing more consistent 24-hour blood pressure control, which may lead to better adherence with once-daily dosing.
- Losartan usually starts at 50 mg once daily, potentially increasing to 100 mg, while olmesartan starts at 20 mg once daily, increasing to 40 mg if needed.
- Both medications are well-tolerated, with similar side effect profiles including dizziness, headache, and occasional hyperkalemia.
- However, olmesartan may be more effective in reducing proteinuria in patients with kidney disease, as suggested by the 2021 KDIGO clinical practice guideline for the management of blood pressure in chronic kidney disease 1.
Key Considerations
- The choice between losartan and olmesartan should consider individual patient factors such as severity of hypertension, kidney function, and cost, as olmesartan is often more expensive.
- Patients should be monitored for blood pressure response, renal function, and potassium levels regardless of which medication is chosen.
- The superior potency of olmesartan is attributed to its stronger binding affinity to the angiotensin II type 1 receptor, resulting in more complete blockade of the renin-angiotensin system, as noted in the 2018 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.
From the Research
Comparison of Losartan and Olmesartan
- Both Losartan and Olmesartan are Angiotensin II receptor antagonists used to treat hypertension [(2,3,4,5,6)].
- Studies have shown that Olmesartan is more effective than Losartan in reducing blood pressure [(2,3,6)].
- Olmesartan has been found to be more effective in reducing proteinuria in patients with chronic kidney disease compared to Losartan 3.
- The pharmacological properties of Olmesartan and Losartan differ, with Olmesartan having a higher receptor affinity and a longer duration of action [(4,5)].
- Clinical trials have demonstrated that Olmesartan is safe and well-tolerated, with an adverse event profile similar to placebo [(5,6)].
Efficacy Comparison
- A study comparing Olmesartan 10 mg/d to Losartan 50 mg/d found that Olmesartan was significantly more effective in reducing blood pressure at weeks 2,4, and 12 2.
- Another study found that Olmesartan 20 mg/d was more effective than Losartan 50 mg/d in reducing blood pressure in patients with mild to moderate hypertension 2.
- Olmesartan has also been shown to be more effective than Losartan in reducing urinary protein in patients with chronic kidney disease 3.
Pharmacological Properties
- Olmesartan is an orally administered prodrug with a high receptor affinity and a long duration of action [(4,5)].
- Losartan, on the other hand, has a shorter duration of action and a lower receptor affinity compared to Olmesartan 4.
- The differences in pharmacological properties between Olmesartan and Losartan may contribute to their differing efficacies in reducing blood pressure and proteinuria [(4,5)].