Sacubitril / valsartan (Entresto) and losartan (Cozaar) are both medications used to treat heart-related conditions, but they belong to different medication classes. Sacubitril / valsartan is an angiotensin receptor-neprilysin inhibitor (ARNI) and is specifically approved for treating heart failure in people ages 1 year and older. Losartan, on the other hand, is an angiotensin II receptor blocker (ARB) and is primarily used to lower high blood pressure, reduce the risk of stroke, and slow kidney problems in people with Type 2 diabetes. Sacubitril / valsartan is taken twice daily and is not available as a generic, while losartan is taken once daily and is available as a lower-cost generic. Common side effects of sacubitril / valsartan include low blood pressure, high potassium levels, and dizziness, whereas losartan may cause dizziness, fatigue, and upper respiratory infections. Both medications can raise potassium levels, so you should avoid taking them with other medications that do the same. Additionally, neither medication should be taken with other ARBs or angiotensin-converting enzyme (ACE) inhibitors due to the risk of angioedema.