What is Cozaar?

Cozaar is in a group of drugs called angiotensin II receptor antagonists. Cozaar and the other drugs in this group prevent blood vessels from narrowing, which helps to lower blood pressure and improve blood flow.

Cozaar is used to treat hypertension (high blood pressure) and can also be used to lower the risk of stroke in certain people with heart disease.

For people with type-2 diabetes and high blood pressure, Cozaar is used to slow long-term kidney damage.

Important Information

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

You should not drink alcohol while taking Cozaar as it can further lower your blood pressure and may increase certain side effects of the medication.

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

You should visit your doctor often to have your blood pressure checked while on Cozaar.

Keep taking the medication even if you feel fine.

In rare cases, use of Cozaar can result in the breakdown of skeletal muscle tissue, leading to kidney failure. If you experience any of the following you should call your doctor right away:

  • muscle pain;
  • tenderness, or weakness especially if you also have fever;
  • nausea or vomiting; and
  • dark colored urine.

Special note: high blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life. Consult with your physician about a comprehensive management program for your high blood pressure which may include medicine, weight loss, exercise, and dietary changes.

What should I know before taking Cozaar?

Below are guidelines you should follow when taking Cozaar:

If you have any of the following conditions or doctor may need to adjust your dose or perform special tests prior to you being able to use Cozaar: kidney disease, liver disease, congestive heart failure, an electrolyte imbalance (such as low levels of potassium in your blood), or if you are dehydrated.

Cozaar can be fatal to an unborn baby. Do not take Cozaar while you are pregnant and notify your doctor immediately if you take the medication in the second or third trimester. Also notify your doctor immediately if you become pregnant while taking Cozaar.

It is not known whether the active ingredient in Cozaar, losartan, can pass into breast-milk and harm a nursing baby. Regardless, you should tell your doctor prior to taking Cozaar if you are currently nursing.


The primary ingredient in Cozaar is losartan potassium.

Side effects of Cozaar

  • pain in your legs or back;
  • stomach pain, diarrhea;
  • muscle cramps;
  • headache, dizziness;
  • cold or flu symptoms such as stuffy nose, sneezing, sore throat, fever;
  • dry cough;
  • tired feeling; or
  • sleep problems (insomnia).

Frequently Asked Questions

Will Cozaar cure my hypertension or angina?

No. Hypertension and other heart conditions are complicated medical conditions that require constant management and monitoring. Although some patients may eventually revert to normalcy, others may require a medication like Cozaar for the rest of their lives to properly manage hypertension.

What’s in Cozaar?

The primary ingredient in Cozaar is losartan potassium.

How does Cozaar work?

Cozaar works by reducing the effectiveness of the chemical angiotensin II in the body which is responsible for narrowing the blood vessels. By doing this, Cozaar can effectively keep the blood vessels wider which means a lower blood pressure and less work on the heart to pump blood through the body.

Are there any drugs I can’t take in combination with Cozaar?

You should discuss any drugs you are currently taking with your doctor before beginning a treatment with Cozaar. Some drugs include lithium (Eskalith, LithoBid, Lithonate), a diuretic such as a water pill, celecoxib (Celebrex), or aspirin or other NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen (Motrin, Advil), diclofenac (Cataflam, Voltaren), etodolac (Lodine), indomethacin (Indocin), nabumetone (Relafen), naproxen (Aleve, Naprosyn), meloxicam (Mobic), piroxicam (Feldene), and others.

Can Cozaar cause an allergic reactions? If so, what are the signs?

You should seek immediate, emergency medical help if you experience any of the following allergic reactions including hives, difficulty breathing, swelling of the face, lips, tongue, or throat.

What happens if I miss a dose of Cozaar?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up any missed doses.