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    Heart Failure Treatment: Potassium and Magnesium

    Potassium and magnesium are often prescribed to heart patients taking diuretics, or ''water pills.'' They replace fluids you lose because of the water pills.

    Examples of potassium supplements include:

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    Magnesium supplements include:

    • Magnesium glycinate
    • Mag-Ox
    • Uro-Mag


    How Do I Take Potassium and Magnesium Supplements?

    Take potassium and magnesium supplements right after meals or with food. Follow the label on how often to take it. The number of doses you take each day, the time between doses, and how long you take it will depend on which medicines you were prescribed and your condition.

    What Are the Side Effects of Potassium and Magnesium Supplements?

    Possible side effects of potassium and magnesium supplements include:

    Nausea, vomiting , diarrhea , and abdominal discomfort. If these side effects continue, call your doctor. If you take controlled-release tablets or capsules and have severe vomiting, vomit blood, or have abdominal pain or swelling, stop taking the medication and call your doctor right away.

    Black, tarry, or bloody stools. These are signs of stomach bleeding. If you have them, call your doctor right away.

    You should also call your doctor if you have:

    • Confusion
    • Irregular or slow heartbeat
    • Numbness
    • Tingling in hands, feet, or lips
    • Shortness of breath or trouble breathing
    • Anxiety
    • Unusual tiredness or weakness

    Should I Avoid Certain Foods or Drugs While Taking Potassium and Magnesium?

    If you are taking magnesium or potassium supplements, let your doctor know if:

    • You are using a salt substitute (many salt substitutes contain potassium).
    • You are using ACE inhibitors or certain diuretics.
    • You have a kidney disorder.
    • You are taking any other supplements.

    Other Guidelines for Taking Potassium and Magnesium

    While taking potassium or magnesium, have your blood pressure checked regularly as advised by your doctor.

    Keep all appointments with your doctor and the lab so that he can see how you're responding to the supplements.

    WebMD Medical Reference

    Reviewed by Suzanne R. Steinbaum, MD on July 27, 2014

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