Hydrochlorothiazide

Common brand names: Esidrix, HydroDIURlL, Oretic and others

Why is hydrochlorothiazide 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 eliminate unneeded water and salt into the urine.

When should hydrochlorothiazide be used?
Hydrochlorothiazide is usually taken one or two times a day. Follow the instructions on the prescription label carefully, and ask your pharmacist or doctor to explain any part that you do not understand.

If you are to take hydrochlorothiazide once a day, take it in the morning. If you are to take it more than once a day, take the last dose in the middle of the afternoon so that you will not have to go to the bathroom during the night.

If you are taking this medication for high blood pressure, it will help control it but will not cure it. NEVER stop taking this medication without talking to your doctor--even if you feel well and expect to keep your blood pressure down.

How should it be used?
Hydrochlorothiazide comes in tablets and oral liquid. The prescription label tells you how much to take at each dose. Take this medication with meals or a snack. You may obtain a specially marked spoon from your pharmacist to measure an accurate dose of the liquid. Ask your pharmacist any questions you have about refilling your prescription.

What special instructions should I follow while using this drug?
Keep all appointments with your doctor. Your blood pressure should be checked regularly, and blood tests should be done occasionally. Do not stop taking hydrochlorothiazide without consulting your doctor.

Be sure that you always have enough of this medication on hand. Check your supply before vacations and other occasions when you may be unable to obtain it.

What special dietary instructions should I follow while using this drug?
Your doctor may instruct you to follow a daily exercise program, to eat a low-salt or low-sodium diet, to take potassium supplements and to add potassium-rich foods (such as, bananas and orange juice) to your diet. Follow these recommendations carefully, since this medication may cause loss of potassium from the body.

What should I do if I forget to take a dose?
Take the missed dose if you remember it on the same day and continue your regular dosing schedule. However, if you remember the missed dose when it is time to take your next dose, take only one dose. Do not take a double dose.

What side effects can this drug cause? What can I do about them?
Although side effects from hydrochlorothiazide are not common, these the following can occur:

• Frequent urination
  This problem should disappear after you take this drug for a few weeks.
• Muscle weakness, cramps, increased thirst, dryness of mouth, mood changes, weak or irregular heart beat, unusual tiredness or weakness (These symptoms may be signs of too much potassium loss.)
  Be sure that you are taking your potassium supplement correctly, if prescribed. Contact your doctor if these symptoms persist.
• Sore throat, easy bruising, skin rash
  Contact your doctor immediately.
• Dizziness, lightheadedness
  Try getting up more slowly from a seated or lying position. If these effects persist or are severe, contact your doctor.
• Confusion, convulsions, decreased mental activity, irritability, muscle cramps (These symptoms may be signs of too much sodium loss.)
  Contact your doctor if these symptoms persist.

* If you experience any other side effects that you think could be caused by this medication and/or are of concern to you, call your doctor.

What other precautions should I follow while using this drug?
Before taking hydrochlorothiazide, tell your doctor:

• If you have kidney or liver disease, diabetes, gout or an allergy to sulfa drugs
• If you develop severe vomiting or diarrhea
• What prescription and nonprescription (over-the-counter) drugs you are taking, especially lithium, probenecid, medication for arthritis or pain, sleeping pills, and other medication for high blood pressure (Also inform your pharmacist.) If you are taking cholestyramine, take it at least one hour after hydrochloro-thiazide. In addition, tell your doctor and pharmacist the names of any vitamins, herbals, and dietary supplements you also may be taking.
• If you are pregnant or breastfeeding (If you become pregnant, contact your doctor immediately.)

Alcohol and sleep aids may cause dizziness or lightheadedness. Ask your doctor or pharmacist for advice about the safe use of alcohol and other medications.

Before having surgery, including dental surgery, tell the doctor about your blood pressure medication. Never share your medication with anyone.

What storage conditions are necessary for this drug?

• Keep hydrochlorothiazide in its original container, with the lid tightly closed.
• Keep this and other medications out of the reach of children.
• Store this drug at room temperature.
• Never take outdated medications. Some medication prescription labels list an expiration date. If such a date is not on your medication label or if you are unsure how old a medication is, call your pharmacy.

This handout summarizes information to help you understand and safely take your medication. Other information--not included in this handout--may be important for you to know because of your unique health status. Ask your doctor and/or pharmacist for more information on the medications prescribed for you and your unique health care needs.