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  1. Losartan oral tablet is available as a brand-name drug and a generic drug. Brand name: Cozaar.
  2. Losartan comes only as a tablet you take by mouth.
  3. Losartan is used to treat hypertension (high blood pressure). It’s also used to help your kidneys work better if you have diabetes. In addition, it’s used to reduce your risk of a stroke if you have high blood pressure and a heart condition called left ventricular hypertrophy.

Losartan is a prescription drug. It comes as an oral tablet.
Losartan is available as the brand-name drug Cozaar. It’s also available as a generic drug. Generic drugs usually cost less than the brand-name version. In some cases, they may not be available in every strength or form as the brand-name drug.
Losartan may be taken as part of a combination therapy with other medications to lower your blood pressure.

What’s losartan used for?

Losartan is used for three main purposes. It’s used to:
  • treat high blood pressure
  • reduce your risk of a stroke if you have high blood pressure and left ventricular hypertrophy (LVH), a condition that causes the walls in the heart’s left ventricle to thicken
  • treat diabetic nephropathy, which is kidney disease caused by diabetes

Losartan drug class

Losartan belongs to a class of drugs called angiotensin receptor blockers (ARBs). A class of drugs is a group of medications that work in a similar way. They’re often used to treat similar conditions.
Other ARBs include olmesartan, valsartan, and telmisartan. Like losartan, these drugs can be used to treat high blood pressure.

How losartan works

Losartan works by blocking the action of angiotensin II, a chemical in your body that causes your blood vessels to tighten and narrow. Losartan helps relax and widen your blood vessels. This lowers your blood pressure.
This action helps treat high blood pressure as well as the other two conditions losartan is usually prescribed for. High blood pressure and left ventricular hypertrophy (LVH) increase your risk of stroke, so lower blood pressure reduces your risk.
Lower blood pressure also reduces your risk of kidney damage. This is because high blood pressure raises your risk of kidney damage that’s caused by the high blood sugar levels linked with diabetes.





Losartan can cause mild or serious side effects. The following list contains some of the key side effects that may occur while taking losartan. This list does not include all possible side effects.
For more information on the possible side effects of losartan, or tips on how to deal with a troubling side effect, talk with your doctor or pharmacist.

More common side effects

The more common side effects that can occur with losartan include:
  • upper respiratory infections, such as the common cold
  • dizziness
  • stuffy nose
  • back pain
  • diarrhea
  • fatigue
  • low blood sugar
  • chest pain
  • high or low blood pressure
These effects may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:
  • High potassium blood levels. Symptoms can include:
    • heart rhythm problems
    • muscle weakness
    • slow heart rate
  • Allergic reactions. Symptoms can include:
    • swelling of your face, lips, throat, or tongue
  • Low blood pressure. Symptoms can include:
    • feeling faint or dizzy
  • Kidney disease. Symptoms can include:
    • swelling in your feet, ankles, or hands
  • unexplained weight gain