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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: potassium supplements
Brand name(s): K-LOR, KAOCHLOR, KAON-CL, KATO, KAY/CIEL, KLOTRIX, MICRO-K, SLOW-K
GENERIC: not available FAMILY: Minerals
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: extended release potassium supplements (eks TEN ded re LEES poh TASS ee um)
Brand name(s): K-DUR, K-TABS
GENERIC: available FAMILY: Other Heart Drugs
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

No data is available on the use of potassium supplements during pregnancy. Use during pregnancy only for clear medical reasons. Tell your doctor if you are pregnant or thinking of becoming pregnant before you take this drug.

Breast-feeding Warning

There is no information on the use of potassium supplements during nursing. There should be no problem as long as the mother’s potassium levels do not get too high.

Facts About This Drug [top]

If you need to get more of the mineral potassium, the safest and least expensive way is to eat more potassium-rich foods daily (see section on potassium supplementation for a discussion of dietary potassium). When researchers compared people eating a potassium-rich diet, people taking potassium supplements, and people taking drugs designed to keep potassium in the body, they found the following: (1) diet is the safest way to replace potassium and (2) potassium supplements and...

If you need to get more of the mineral potassium, the safest and least expensive way is to eat more potassium-rich foods daily (see section on potassium supplementation for a discussion of dietary potassium). When researchers compared people eating a potassium-rich diet, people taking potassium supplements, and people taking drugs designed to keep potassium in the body, they found the following: (1) diet is the safest way to replace potassium and (2) potassium supplements and potassium-sparing drugs return potassium levels to normal in only half the people who use them.

Potassium supplements can cause stomach and intestinal ulcers, bleeding, blockage, and perforation. Because of these serious potential adverse effects, you should only take supplements if you have been eating plenty of potassium-rich foods yet still have a low level of potassium in your blood (less than 3 millimoles per liter of blood).[1] Also, you should only take potassium supplements if you have adequate kidney function. The safest form of potassium supplement is an oral solution (liquid) of potassium chloride, and you should only use other forms if you cannot tolerate the liquid. However, enteric-coated potassium products should never be taken.

Before You Use This Drug [top]

Do not use if you have or have had:

  • Addison’s disease
  • prolonged and severe diarrhea
  • heart disease
  • intestinal blockage
  • kidney disease or decreased urine production
  • stomach ulcer
  • high blood potassium levels

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • If you have black, tarry stools or bloody vomit, call your doctor immediately. These are signs of stomach or intestinal bleeding.
  • Schedule regular appointments with your doctor to check your progress.
  • Check with your doctor before using salt substitutes, low-salt milk, or other low-salt foods. Because these foods often contain potassium, your potassium supplement dose may have to be adjusted to avoid getting dangerously high levels of potassium in your blood.
  • Ask your doctor whether you should supplement your diet with vitamin B12. Your body may not be able to absorb this vitamin as well while you are taking potassium supplements.

How to Use This Drug [top]

  • If you miss a dose, take it within two hours of the time you were supposed to take it. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take with, or immediately after, meals. If you are taking extended-release tablets or capsules, swallow them whole, without chewing or crushing them. Take tablets with a full glass (eight ounces) of water. Take your last dose of the day with a full glass of water at least an hour before bedtime. Taking this drug with food may help prevent stomach irritation. If you are taking a solution, dissolvable tablet, or powder, dissolve it completely in at least half a glass (four ounces) of juice or cold water, then sip slowly over a five- to ten-minute period. Do not use tomato juice, which has a high salt content.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Do not allow the liquid form to freeze. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers, potassium-sparing diuretics, salt substitutes.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • confusion
  • irregular heartbeat
  • numbness or tingling in hands, feet, or lips
  • unusual tiredness or weakness
  • weakness or heaviness of legs
  • difficulty breathing
  • unexplained anxiety
  • abdominal or stomach pain, cramping, or soreness
  • chest or throat pain
  • bloody or black tarry stools

Call your doctor if these symptoms continue:

  • diarrhea
  • nausea or vomiting
  • stomach pain, discomfort, or gas

These adverse effects can be reduced by taking potassium with food or by using more liquid (water or juice) to dilute it.

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • heart function tests, such as electrocardiogram (ECG, EKG)
  • kidney function tests
  • blood potassium or magnesium levels
  • blood pH and bicarbonate levels

last reviewed June 30, 2021