Cozaar (losartan) is used to treat hypertension (or high blood pressure) in patients at least six years old as well as to treat slow, long-term kidney damage in patients with type 2 diabetes who also have hypertension. It may also be used to lower the risk of stroke in some patients with heart disease. Cozaar is an angiotensin II receptor antagonist and it keeps blood vessels from getting narrow, improving blood flow.
This medication has not been approved to be used by patients under six.
The Cozaar generic name is losartan.

Carefully follow your doctor’s instructions and any guidance you may receive along with your medicine. Your doctor may adjust your dose occasionally. You may need to undergo regular blood, urine, and blood pressure tests.

Blood pressure may not improve until after three to six weeks of treatment. Consult with your doctor if your condition does not improve after three weeks. Keep taking this medication even if you feel well because high blood pressure often doesn’t show symptoms.

Cozaar/losartan can be taken with or without food. If you miss a dose, take your medicine as soon as possible, but skip the missed dose if it’s almost time for the next one.

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

Do not use Cozaar (losartan) if you are allergic to it. Before starting on losartan, tell your doctor if you’ve experienced kidney or liver disease, congestive heart failure, electrolyte imbalance, or if you are dehydrated or on a low-salt diet.

Diabetic patients should not use Cozaar with any medicine that contains aliskiren. Patients with kidney disease may also need to avoid taking Cozaar (losartan).

Pregnant patients should not use this drug. Inform your doctor if you are pregnant or plan to. Do not breast-feed while using this medicine.

Avoid getting up too quickly from sitting or lying down. Dizziness may result.

In rare circumstances, losartan can cause a breakdown of skeletal muscle tissue that can lead to kidney failure. So contact your doctor immediately if you experience unexplained muscle pain, tenderness, or weakness, especially if you also experience unusual fatigue, fever, and dark urine.

Using this drug can easily cause dehydration. This can result in very low blood pressure, a serious electrolyte imbalance, or kidney failure. Call your doctor if you experience unusual sweating, vomiting, or diarrhea.

Find emergency medical attention if you suspect an allergic reaction, such as hives or swelling. Also contact your doctor immediately if you feel: lightheaded, painful or burning urination, symptoms of high potassium (nausea, weakness, tingling, chest pain, irregular pulse, loss of movement), and symptoms of kidney issues (little/no urination, rapid weight gain, painful/difficult urination, swelling in hands, feet, or ankles).

Other common side effects include dizziness, back pain, and cold symptoms. Please note this guide does not contain all possible side effects and drug interactions.

What can Cozaar/losartan interact with?

Alcohol use may increase side effects and further lower your blood pressure.

Don’t take potassium supplements or salt substitutes unless directed by a doctor. Tell your doctor about other drugs you use, especially if you use diuretics, other blood pressure drugs, lithium, or NSAIDs like aspirin and ibuprofen. Also mention any over-the-counter drugs, vitamins, supplements, and herbs.