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Heart Failure Health Center

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Heart Failure Treatment With Potassium and Magnesium Supplements

Potassium and magnesium are important in controlling blood pressure. They are often prescribed to heart patients taking diuretics, or ''water pills.'' They replace fluids lost through increased urination caused by diuretics.

Potassium supplements include:

Recommended Related to Heart Failure

Understanding Heart Failure -- Prevention

Drug therapy to lower blood pressure has been shown to reduce heart failure rates by 40%-60%. Reducing blockages in the coronary arteries with anti-cholesterol drugs has been shown to reduce heart failure rates by 30%. Early diagnosis and treatment of heart-valve abnormalities can prevent heart failure caused by chronic volume overload of the heart's left chamber.

Read the Understanding Heart Failure -- Prevention article > >

Magnesium supplements include:

  • Mag-Ox
  • Uro-Mag
  • Magnesium glycinate

How Do I Take Potassium and Magnesium Supplements?

Take potassium and magnesium supplements right after meals or with food. Follow the label directions on how often to take it. The number of doses you take each day, the time allowed between doses, and how long you need to take it will depend on the type of medication prescribed, as well as 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.; take the medication with food or right after meals with a full glass of water. If these side effects continue, contact your doctor. If you take controlled-release tablets or capsules and experience severe vomiting or vomit blood and abdominal pain or swelling, stop taking the medication and contact your doctor right away.
  • Black, tarry, or bloody stools (signs of stomach bleeding); contact your doctor right away.
  • Confusion; irregular or slow heartbeat; numbness or tingling in hands, feet, or lips; shortness of breath or difficult breathing; unexplained anxiety; unusual tiredness, or weakness. Contact your doctor right away.

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 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 your response to the drug can be monitored.

WebMD Medical Reference

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

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