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URL of this page: https://medlineplus.gov/druginfo/meds/a601099.html

Potassium

pronounced as (poe tass' i um)

Why is this medication prescribed?

Potassium is essential for the proper functioning of the heart, kidneys, muscles, nerves, and digestive system. Usually the food you eat supplies all of the potassium you need. However, certain diseases (e.g., kidney disease and gastrointestinal disease with vomiting and diarrhea) and drugs, especially diuretics ('water pills'), remove potassium from the body. Potassium supplements are taken to replace potassium losses and prevent potassium deficiency.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Potassium comes in oral liquid, powder, granules, effervescent tablets, regular tablets, extended-release (long-acting) tablets, and extended-release capsules. It usually is taken two to four times a day, with or immediately after meals. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take potassium exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Take all forms of potassium with a full glass of water or fruit juice.

Add the liquid to water. Dissolve the powder, granules, or effervescent tablets in cold water or fruit juice according to the manufacturer's directions or the directions on your prescription label; mix the drug well just before you take it. Cold liquids help mask the unpleasant taste.

Swallow extended-release tablets and capsules whole. Do not chew them or dissolve them in your mouth.

What special precautions should I follow?

Before taking potassium,

  • tell your doctor and pharmacist if you are allergic to potassium or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially angiotensin converting enzyme (ACE) inhibitors such as captopril (Capoten), enalapril (Vasotec),and lisinopril (Prinivil, Zestril); diuretics ('water pills'); and vitamins. Do not take potassium if you are taking amiloride (Midamor), spironolactone (Aldactone), or triamterene (Dyrenium).
  • tell your doctor if you have or have ever had heart, kidney, or Addison's (adrenal gland) disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking potassium, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking potassium.

What special dietary instructions should I follow?

If you are using a salt substitute, tell your doctor. Many salt substitutes contain potassium. Your doctor will consider this source in determining your dose of potassium supplement. Your doctor may advise you to use a potassium-containing salt substitute and to eat potassium-rich foods (e.g., bananas, prunes, raisins, and milk).

What should I do if I forget a dose?

Take the missed dose as soon as you remember it and take any remaining doses for that day at evenly spaced intervals. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Potassium may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • upset stomach
  • vomiting
  • diarrhea

If you experience any of the following symptoms, call your doctor immediately:

  • mental confusion
  • listlessness
  • tingling, prickling, burning, tight, or pulling sensation of arms, hands, legs, or feet
  • heaviness or weakness of legs
  • cold, pale, gray skin
  • stomach pain
  • unusual stomach bulging
  • black stools

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to potassium. You may have electrocardiograms (EKGs) and blood tests to see if your dose needs to be changed.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Glu-K®
  • K+ 10®
  • K+ 8®
  • K+ Care®
  • K+ Care® Effervescent Tablets
  • Kaochlor® 10%
  • Kaon® Elixir
  • Kaon-Cl® 20% Elixir
  • Kaon-Cl-10®
  • Kay Ciel®
  • K-Dur® 10
  • K-Dur® 20
  • K-Lor®
  • Klor-Con® 10
  • Klor-Con® 8
  • Klor-Con® Powder
  • Klor-Con®/25 Powder
  • Klor-Con®/EF
  • Klotrix®
  • K-Lyte/CL® 50 Effervescent Tablets
  • K-Lyte/CL® Effervescent Tablets
  • K-Lyte® DS Effervescent Tablets
  • K-Lyte® Effervescent Tablets
  • K-Tab® Filmtab®
  • Micro-K®
  • Quic-K®
  • Rum-K®
  • Slow-K®
  • Tri-K®
  • Twin-K®

Other names

  • KCl

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 11/15/2015