Key takeaways
Losartan (Cozaar) and atenolol (Tenormin) are both medications used to treat high blood pressure, but they belong to different medication classes. Losartan is an angiotensin II receptor blocker (ARB), while atenolol is a cardioselective beta blocker. Losartan is also FDA-approved to lower the risk of stroke in people with high blood pressure and a thickened heart (left ventricular hypertrophy), and to slow kidney problems in people with Type 2 diabetes. Atenolol, on the other hand, is approved for treating chest pain (angina) and reducing the risk of death after a heart attack. Losartan is typically taken once daily, at a dose of 25 mg to 100 mg, and is available as a lower-cost generic. Atenolol is also taken once daily, at a dose ranging from 25 mg to 200 mg per day, but can be taken twice daily in some cases. Common side effects of losartan include dizziness and upper respiratory infections, while atenolol can cause tiredness and cold hands and feet, in addition to dizziness. Losartan can interact with nonsteroidal anti-inflammatory drugs (NSAIDs) and medications that raise potassium levels. Both losartan and atenolol can interact with other blood pressure medications, increasing the risk of low blood pressure (hypotension).
