MedlinePlus Drug Information: Hydrochlorothiazide

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Hydrochlorothiazide

(hye droe klor oh thye' a zide)

Brand name(s): Esidrix; HydroDIURIL; Oretic

Contents of this page:
Why is this medication prescribed? How should this medicine be used? Other uses for this medicine What special precautions should I follow? What special dietary instructions should I follow?	What should I do if I forget a dose? What side effects can this medication cause? What storage conditions are needed for this medicine? In case of emergency/overdose What other information should I know?

Why is this medication prescribed?

Hydrochlorothiazide, a 'water pill,' is used to treat high blood pressure and fluid retention caused by various conditions, including heart disease. It causes the kidneys to get rid of unneeded water and salt from the body into the urine.

This medicine is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Hydrochlorothiazide comes as a tablet and liquid to take by mouth. It usually is taken once or twice a day. If you are to take it once a day, take it in the morning; if you are to take it twice a day, take it in the morning and in the late afternoon to avoid going to the bathroom during the night. Take this medication with meals or a snack. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take hydrochlorothiazide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Hydrochlorothiazide controls high blood pressure but does not cure it. Continue to take hydrochlorothiazide even if you feel well. Do not stop taking hydrochlorothiazide without talking to your doctor.

Other uses for this medicine

Hydrochlorothiazide also may be used to treat patients with diabetes insipidus and certain electrolyte disturbances and to prevent kidney stones in patients with high levels of calcium in their blood. Talk to your doctor about the possible risks of using this medicine for your condition.

What special precautions should I follow?

Before taking hydrochlorothiazide,

tell your doctor and pharmacist if you are allergic to hydrochlorothiazide, sulfa drugs, or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially other medicines for high blood pressure, anti-inflammatory medications such as ibuprofen (Motrin, Nuprin) or naproxen (Aleve), corticosteroids (e.g., prednisone), lithium (Eskalith, Lithobid), medications for diabetes, probenecid (Benemid), and vitamins. If you also are taking cholestyramine or colestipol, take it at least 1 hour after hydrochlorothiazide.
tell your doctor if you have or have ever had diabetes, gout, or kidney, liver, thyroid, or parathyroid disease.
tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking hydrochlorothiazide, call your doctor immediately.
if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking hydrochlorothiazide.
you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how this drug affects you.
remember that alcohol can add to the drowsiness caused by this drug.
plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Hydrochlorothiazide may make your skin sensitive to sunlight.

What special dietary instructions should I follow?

Follow your doctor's directions. They may include following a daily exercise program or a low-salt or low-sodium diet, potassium supplements, and increased amounts of potassium-rich foods (e.g., bananas, prunes, raisins, and orange juice) in your diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Frequent urination should go away after you take hydrochlorothiazide for a few weeks. Tell your doctor if any of these symptoms are severe or do not go away:

muscle weakness
dizziness
cramps
thirst
stomach pain
upset stomach
vomiting
diarrhea
loss of appetite
headache
hair loss

If you experience any of the following symptoms, call your doctor immediately:

sore throat with fever
unusual bleeding or bruising
severe skin rash with peeling skin
difficulty breathing or swallowing

What storage conditions are needed for this medicine?

Keep this medicine in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Do not allow the oral liquid to freeze. Throw away any medicine that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medicine.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly, and blood tests should be done occasionally.

Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer