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Heart Disease Health Center

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Heart Disease and Diuretics

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How Should I Take Diuretics?

Before a diuretic is prescribed, tell your doctor if you have diabetes, kidney disease, liver disease, or gout.

Follow the label directions on how often you should take the diuretic. If you are taking a single dose a day, take it in the morning with your breakfast or right after eating your breakfast. If you are taking more than one dose a day, take the last dose no later than 4 p.m.

The number of doses you take each day, the time allowed between doses, and how long you need to take a diuretic will depend on the type prescribed, as well as your condition.

Weigh yourself at the same time every day (on the same scale) and record your weight. Call your doctor if you gain three pounds in one day or five pounds in one week.

While taking a diuretic, have your blood pressure and kidney function tested regularly, as advised by your doctor. These tests are important because diuretics can change your blood potassium and magnesium levels.

Keep all appointments with your doctor and the laboratory so that your response to this medication can be monitored.

What Are the Side Effects of Diuretics?

Diuretics can cause the following side effects:

  • Frequent urination. This may last for up to four hours after each dose. If you are taking two diuretic doses each day, take the second dose no later than late afternoon so you can sleep through the night without needing to wake up to urinate..
  • Extreme tiredness or weakness. These effects should decrease as your body adjusts to the medication. Call your doctor or nurse if these symptoms persist, since these symptoms could mean your medication dose needs to be adjusted.
  • Muscle cramps or weakness. Be sure that you are taking your potassium supplement correctly, if prescribed. Contact your doctor or nurse if these symptoms persist.
  • Thirst. Try sucking on sugarless hard candy. Contact your doctor or nurse if you have extreme thirst, which could be a sign of dehydration.
  • Dizziness, lightheadedness. Try rising more slowly when getting up from a lying or sitting position.
  • Blurred vision, confusion, headache, increased perspiration (sweating), restlessness. If these effects are persistent or severe, contact your doctor or nurse.
  • Dehydration. Signs include dizziness, extreme thirst, excessive dryness of the mouth, decreased urine output, dark-colored urine, or constipation. If these symptoms occur, don't assume you need more fluids -- call your doctor or nurse.
  • Fever , sore throat, cough, ringing in the ears, unusual bleeding or bruising, rapid and excessive weight loss. Contact your doctor or nurse right away.
  • Skin rash. Stop taking the medication and contact your doctor or nurse right away.
  • Loss of appetite, nausea, vomiting, or muscle cramps. Be sure that you are taking your potassium supplement correctly, if prescribed. Contact your doctor or nurse if these symptoms persist.

Contact your doctor or nurse if you have any other symptoms that cause concern.

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