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Medications and Drugs

Brand Names: Diuril

Generic Name: chlorothiazide (Pronunciation: KLOR oh THYE a zide)

What is chlorothiazide (Diuril)?

Chlorothiazide is a thiazide diuretic (water pill) that helps prevent your body from absorbing too much salt, which can cause fluid retention.

Chlorothiazide treats fluid retention (edema) in people with congestive heart failure, cirrhosis of the liver, or kidney disorders, or edema caused by taking steroids or estrogen. This medication is also used to treat high blood pressure (hypertension).

Chlorothiazide may also be used for other purposes not listed in this medication guide.

Chlorothiazide 250 mg-MYL

round, white, imprinted with M 50

Chlorothiazide 500 mg-MYL

round, white, imprinted with MYLAN 162

Diuril 250 mg

round, white, imprinted with DIURIL, MSD 214

Diuril 500 mg

round, white, imprinted with DIURIL, MSD432

What are the possible side effects of chlorothiazide (Diuril)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medication and call your doctor at once if you have any of these serious side effects:

  • nausea and vomiting with weakness, loss of appetite, headache, hallucinations, muscle pain, and/or seizure;
  • confusion, uneven heart rate, extreme thirst, leg discomfort, muscle weakness or limp feeling;
  • urinating more or less than usual or not at all;
  • easy bruising or bleeding;
  • numbness or tingly feeling;
  • fever, sore throat, and headache with a severe blistering, peeling, and red skin rash; or
  • jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about chlorothiazide (Diuril)?

Do not use this medication if you are allergic to chlorothiazide or if you are unable to urinate.

Before using this medication, tell your doctor if you are allergic to sulfa drugs, or if you have liver disease, kidney disease, asthma, allergies, gout, lupus, or diabetes.

Avoid drinking alcohol, which can increase some of the side effects of chlorothiazide.

Tell your doctor if you regularly use other medicines that make you light-headed (such as cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to the side effects of chlorothiazide.

Avoid becoming overheated or dehydrated during exercise and in hot weather. Follow your doctor's instructions about the type and amount of liquids you should drink. In some cases, drinking too much liquid can be as unsafe as not drinking enough.

If you are being treated for high blood pressure, keep using this medication even if you feel fine. High blood pressure often has no symptoms.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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