Looking for a clear, no-nonsense overview of Losartan? This page breaks down what Losartan does, who takes it, common side effects, and simple safety tips you can use today. No fluff—just the basics you need to understand this ARB medication.
Losartan is an ARB—angiotensin II receptor blocker. It relaxes blood vessels by blocking a hormone that tightens them, so your blood pressure drops and your heart works easier. Doctors commonly prescribe it for high blood pressure, for protecting the kidneys in people with type 2 diabetes, and sometimes after heart problems. You might hear the brand name Cozaar, but generic losartan is widely available and usually less expensive.
Most adults start on a low dose and the doctor adjusts it based on your blood pressure and tolerance. Typical starting doses are 25–50 mg once daily, and many people take 50 mg. Some patients need up to 100 mg. Your doctor picks the dose for your situation—don’t change it without checking in.
Common side effects are mild: dizziness (especially when you first stand up), headache, or fatigue. Less common but important issues include high potassium (hyperkalemia) and changes in kidney function. Unlike ACE inhibitors, ARBs usually don’t cause a persistent cough, but angioedema (swelling of face, lips, throat) can still happen. If you notice sudden swelling or trouble breathing, get medical help right away.
Certain drugs raise the risk of problems with losartan. Watch out for potassium supplements, salt substitutes that contain potassium, NSAIDs (like ibuprofen), lithium, and other blood pressure drugs that affect the same hormonal system. If you take any of these, mention them to your prescriber so they can adjust treatment or test more often.
Pregnancy and breastfeeding: Losartan can harm an unborn baby, so it’s not for pregnant women. If you’re planning pregnancy or find out you’re pregnant, talk to your doctor immediately to switch medications safely.
Simple monitoring steps make Losartan safer. Check blood pressure regularly, and your doctor will likely test kidney function and potassium levels a few weeks after starting or changing the dose. Keep a log of readings to share at visits—this helps your provider make informed dose changes.
Buying tips: Losartan needs a prescription. Use a licensed pharmacy and watch out for suspicious online sellers. Generic losartan is common and a good cost-saving option. If a deal looks too good or a site asks for no prescription, stop and verify the pharmacy’s credentials.
Questions for your prescriber: Ask why losartan is the right choice for you, what dose they recommend, whether you need blood tests, and what to do if you miss a dose. Those four questions clear up most concerns quickly.
Want more detail on specific conditions or drug interactions? Browse related articles on our site or bring your questions to your healthcare team—losartan works well for many people when used the right way.
