Key takeaways
Losartan (Cozaar) and Atenolol (Tenormin) are both used to treat high blood pressure, but they belong to different medication classes and work in different ways. Losartan is an angiotensin II receptor blocker (ARB) that helps relax blood vessels and reduce water retention, while atenolol is a cardioselective beta-blocker that slows down the heart rate to reduce blood pressure and chest pain. Losartan is also used to lower the risk of stroke and slow kidney problems in people with diabetes, whereas atenolol is used to lower the risk of death after a heart attack. Losartan is typically taken once daily and is available as a lower-cost generic, while atenolol is also taken once daily but can be taken twice daily after a heart attack. Common side effects of losartan include dizziness and upper respiratory infections, while atenolol can cause tiredness, dizziness, and cold hands and feet. Neither medication is recommended during pregnancy.
