Olmesartan is used alone or in combination with other medications to treat high blood pressure in adults and children 6 years of age and older. Olmesartan is in a class of medications called angiotensin II receptor antagonists. It works by blocking the action of certain natural substances that tighten the blood vessels, allowing the blood to flow more smoothly and the heart to pump more efficiently.

High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

Olmesartan comes as a tablet to take by mouth. It is usually taken once a day with or without food. To help you remember to take olmesartan, take it at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take olmesartan exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

If your child can not swallow a tablet, talk to your doctor or pharmacist. The pharmacist can prepare a liquid form of this medication for your child.

Your doctor will probably start you on a low dose of olmesartan and may increase your dose after 2 weeks.

Olmesartan controls high blood pressure but does not cure it. Your blood pressure may decrease during the first week of your treatment, but it may take up to 2 weeks before you notice the full benefit of olmesartan. Continue to take olmesartan even if you feel well. Do not stop taking olmesartan without talking to your doctor.

Olmesartan is also sometimes used to treat heart failure (condition in which the heart is unable to pump enough blood to the rest of the body) and diabetic nephropathy (kidney disease in people with diabetes and high blood pressure). Talk to your doctor about the possible risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking olmesartan,

• tell your doctor and pharmacist if you are allergic to olmesartan, any other medications, or any of the ingredients in olmesartan tablets. Ask your pharmacist for a list of the ingredients.
• tell your doctor if you have diabetes (high blood sugar) and are taking aliskiren (Tekturna, in Amturnide, Tekamlo, Tekturna HCT, Valturna). Your doctor will probably tell you not to take olmesartan if you have diabetes and are also taking aliskiren.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: an angiotensin-converting enzyme (ACE) inhibitor such as benazepril (Lotensin, in Lotrel), captopril (Capoten, in Capozide), enalapril (Vasotec), fosinopril, lisinopril (in Prinzide), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril, in Accuretic, in Quinaretic), ramipril (Altace), trandolapril (Mavik, in Tarka); colesevelam (Welchol); diuretics (‘water pills’); gemfibrozil (Lopid); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); and potassium supplements. Your doctor may need to change the doses of your medication or monitor you carefully for side effects.
• tell your doctor if you have or have ever had heart failure, or kidney or liver disease.
• tell your doctor if you are breast-feeding.