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Cozaar

Generic Name: losartan (loe SAR tan)
Brand Names: Cozaar

Medically reviewed by P. Thornton, DipPharm. Last updated on Dec 11, 2018.

What is Cozaar?

Cozaar (losartan) belongs to a group of drugs called angiotensin II receptor antagonists (sometimes called ARB blockers). It keeps blood vessels from narrowing, which lowers blood pressure and improves blood flow.

Cozaar is used to treat high blood pressure (hypertension) in adults and children who are at least 6 years old. It is also used to lower the risk of stroke in certain people with heart disease.

Cozaar is also used to slow long-term kidney damage in people with type 2 diabetes who also have high blood pressure.

Important Information

Do not use Cozaar if you are pregnant, and tell your doctor right away if you become pregnant. Losartan can cause injury or death to the unborn baby during your second or third trimester.

If you have diabetes, do not use Cozaar together with any medication that contains aliskiren (a blood pressure medicine).

You may also need to avoid taking Cozaar with aliskiren if you have kidney disease.

In rare cases, Cozaar can cause a condition that results in the breakdown of skeletal muscle tissue, leading to kidney failure. Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.

Before taking this medicine

You should not use Cozaar if you are allergic to losartan.

Do not use Cozaar if you are pregnant, and tell your doctor right away if you become pregnant. Losartan can cause injury or death to the unborn baby if you take the medicine during your second or third trimester.

To make sure Cozaar is safe for you, tell your doctor if you have:

  • kidney disease;

  • liver disease;

  • congestive heart failure;

  • an electrolyte imbalance (such as high levels of potassium in your blood);

  • if you are on a low-salt diet; or

  • if you are dehydrated.

You should not breast-feed while using Cozaar.

Cozaar is not approved for use by anyone younger than 6 years old.

How should I take Cozaar?

Take Cozaar exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

You may take Cozaar with or without food.

Call your doctor if you are sick with vomiting or diarrhea, or if you are sweating more than usual. You can easily become dehydrated while taking Cozaar. This can lead to very low blood pressure, a serious electrolyte imbalance, or kidney failure.

Your blood pressure will need to be checked often and you may need other blood and urine tests.

It may take 3 to 6 weeks before your blood pressure is under control. For best results, keep using the medicine as directed. Talk with your doctor if your condition does not improve after 3 weeks of treatment.

If you have high blood pressure, keep using this medicine even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

Store at room temperature away from moisture, heat, and light.

Cozaar dosing information

Usual Adult Dose for Diabetic Nephropathy:

Initial dose: 50 mg orally once a day
Maximum dose: 100 mg orally once a day

Comments:
-If hypertensive patients with left ventricular hypertrophy or type 2 diabetic nephropathy patients require titration from initial dose, increase to 100 mg orally once a day.
-Antihypertension is substantially present within 1 week but in some studies the maximal effect occurred in 3 to 6 weeks.

Uses:
-Treatment of hypertension.
-To reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy.
-Treatment of diabetic nephropathy with an elevated serum creatinine and proteinuria (urinary albumin to creatinine ratio 300 mg/g or greater) in patients with type 2 diabetes and a history of hypertension.

Usual Adult Dose for Hypertension:

Initial dose: 50 mg orally once a day
Maximum dose: 100 mg orally once a day

Comments:
-If hypertensive patients with left ventricular hypertrophy or type 2 diabetic nephropathy patients require titration from initial dose, increase to 100 mg orally once a day.
-Antihypertension is substantially present within 1 week but in some studies the maximal effect occurred in 3 to 6 weeks.

Uses:
-Treatment of hypertension.
-To reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy.
-Treatment of diabetic nephropathy with an elevated serum creatinine and proteinuria (urinary albumin to creatinine ratio 300 mg/g or greater) in patients with type 2 diabetes and a history of hypertension.

Usual Pediatric Dose for Hypertension:

6 Years or Older:
Initial dose: 0.7 mg/kg orally once a day (up to 50 mg total)

Comments:
-May be given as a tablet or suspension.
-Doses above 1.4 mg/kg (or 100 mg) daily have not been studied in pediatric patients.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Cozaar?

Drinking alcohol can further lower your blood pressure and may increase certain side effects of Cozaar.

Do not use potassium supplements or salt substitutes, unless your doctor has told you to.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Cozaar side effects

Get emergency medical help if you have signs of an allergic reaction to Cozaar: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • pain or burning when you urinate;

  • high potassium level - nausea, weakness, tingly feeling, chest pain, irregular heartbeats, loss of movement; or

  • kidney problems - little or no urination, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath.

Common Cozaar side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Cozaar?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may interact with losartan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Cozaar only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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