Losartan and hydrochlorothiazide combination is used alone or together with other medicines to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. Lowering blood pressure may reduce the risk of strokes and heart attacks.

Losartan and hydrochlorothiazide combination is also used to reduce the risk of stroke in patients with high blood pressure and enlargement of the heart.

Losartan is an angiotensin II receptor blocker (ARB). It works by blocking a substance in the body that causes the blood vessels to tighten. Losartan relaxes the blood vessels and lowers the blood pressure. A lower blood pressure will increase the supply of blood and oxygen to the heart.

Hydrochlorothiazide is a thiazide diuretic (water pill) . It reduces the amount of water in the body by increasing the flow of urine, which helps lower the blood pressure.

This medicine is available only with your doctor's prescription.

In addition to the use of the medicine your doctor has prescribed, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium (salt). Your doctor will tell you which of these is most important for you. You should check with your doctor before changing your diet.

Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.

Remember that this medicine will not cure your high blood pressure but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.

This medicine may be taken with or without food.

This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.

If you also use cholestyramine or colestipol, take these at least 4 hours after you take this medicine.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Rare

Black, tarry stools

blood in the urine or stools

cough or hoarseness accompanied by chills or fever, lower back or side pain, or painful or difficult urination

fainting

pinpoint red spots on the skin

pounding heartbeat

severe stomach pain, nausea, and vomiting

skin rash

swelling of the feet or lower legs

unusual bleeding or bruising

Incidence not known

Coma

confusion

dark-colored urine

decreased urine output

dry mouth

fast or irregular heartbeat

fever

increased thirst

irritability

large, flat, blue, or purplish patches in the skin

large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs

light-colored stools

muscle cramps or pain

muscle spasms

muscle stiffness

muscle twitching

nausea or vomiting

painful knees and ankles

raised red swellings on the skin, the buttocks, legs, or ankles

restlessness

seizures

shortness of breath

swelling of the face, ankles, or hands

upper right abdominal or stomach pain

unusual tiredness or weakness

weak or irregular heartbeat

yellow eyes and skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

Cold or flu-like symptoms

dizziness

headache

increased sensitivity of the skin to sunlight

sore throat

stomach pain

Rare

Dry cough

sinus problems

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.

This medicine may cause dizziness, lightheadedness, or fainting, especially when you get up suddenly from a lying or sitting position. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy. If you feel dizzy, lie down so you do not faint. Then sit for a few moments before standing to prevent the dizziness from returning.

Check with your doctor right away if you become sick while taking this medicine, especially if you have severe or continuing nausea or vomiting, or diarrhea that does not stop. These conditions may cause you to lose too much water and may lead to low blood pressure. You can also lose water by sweating, so drink plenty of water during exercise or in hot weather.

Check with your doctor immediately if blurred vision, difficulty reading, eye pain, or any other change in vision occurs during or after treatment. This could be a sign of a serious eye problem. Your doctor may want an eye doctor to check your eyes.

This medicine may affect blood sugar levels. Diabetic patients may notice a change in the results of blood or urine glucose tests. Talk to your doctor if you have any questions.

Ask your doctor before you use medicines, supplements, or salt substitutes that contain potassium.

Drinking alcohol or taking narcotic pain relievers or sleeping pills with this medicine may intensify feeling lightheaded, dizzy, or faint. Tell your doctor if you are drinking alcohol or using pain relievers or sleeping pills.

Do not take other medicines unless they have been discussed with your doctor. This especially includes prescription or nonprescription (over-the-counter [OTC]) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, and herbal or vitamin supplements.