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Potassium chloride: 7 things you should know

Medically reviewed by Carmen Fookes, BPharm. Last updated on Dec 28, 2019.

1. How it works

  • Potassium chloride tablets replace potassium in your body.
  • Potassium is a mineral that is found naturally in many foods. Our heart and other organs need potassium to function properly. Potassium levels can become low if you have had a prolonged bout of either diarrhea or vomiting, have been taking diuretics (water pills), or with some diseases.
  • Potassium is classed as a mineral supplement.

2. Upsides

  • Potassium chloride tablets are used to prevent and treat low blood levels of potassium (this is also called hypokalemia).
  • Tablets are designed to release potassium chloride slowly over a period of time.
  • Generic potassium chloride tablets are available.

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Diarrhea, stomach pain, muscle weakness, numbness or tingling in the hands, feet, or mouth, uneven heartbeat. Side effects are more likely if high dosages of potassium chloride are being taken.
  • May not be suitable for some people including those with kidney failure, Addison's disease, severe burns, or severe wounds.
  • Should also not be taken by a person who is dehydrated or has high levels of potassium in their blood.
  • Certain medical conditions such as dysphagia, swallowing disorders, or severe gastrointestinal motility disorders may cause potassium chloride tablets to maintain contact with the gastroinestinal mucosa for long periods of time. Consider the use of liquid potassium in these patients. Potassium chloride tablets should not be taken on an empty stomach.
  • Available as tablets, a powder, and in granulated and liquid form.
  • May interact with several other medicines including digoxin, quinidine, ACE inhibitors, and several diuretics.

Notes: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. For a complete list of all side effects, click here.

4. Bottom Line

Potassium chloride is a mineral used to replenish potassium within our body. It may irritate the stomach; however, other side effects generally only occur with higher dosages.

5. Tips

  • Take with food or just after a meal to reduce the risk of stomach irritation. Take with a full glass of water.
  • Some foods (such as squash, spinach, lentils, kidney beans, orange juice, bananas) are also high in potassium. Ask your doctor if there is a limit to how much of these foods you can eat. Some salt substitutes or low-salt dietary products also contain potassium - be careful how much of these you eat.
  • Do not crush, break, chew or suck extended-release potassium chloride tablets as doing this may cause too much potassium chloride to be released at once, irritating your throat and stomach. Tablets are designed to release potassium slowly over a period of time. Sometimes you may notice the remnants of a potassium chloride tablet in your stool.
  • Can be taken with some diuretics (water pills) but not others. Only take if your doctor has prescribed potassium chloride.
  • Mix the powder, granule or liquid form with water or fruit juice and drink slowly over 5 to 10 minutes.
  • Your doctor may require you to come in for regular blood tests to make sure your potassium chloride tablets are adequately replacing your blood levels of potassium. Sometimes your heart rate may need to be checked as well. Make sure you keep to your scheduled appointments.
  • Contact your doctor straight away if you experience confusion, anxiety, extreme thirst or increased urination, numbness, black or bloody stools, cough up blood, or vomit up black flecks.
  • Do not stop taking potassium chloride without your doctor's advice as it may worsen your condition.
  • Take only as directed. If you miss a dose, take it as soon as you remember, but if you don't remember until the next day, do not take a double-dose.

6. Response and Effectiveness

  • Tablets start disintegrating within a few minutes; however, potassium chloride tablets are released slowly over several hours which reduces the risk of stomach irritation.
  • Potassium chloride is usually taken once daily until potassium levels are within the normal range.

7. Interactions

Medicines that interact with potassium chloride may either decrease its effect, affect how long it works for, increase side effects, or have less of an effect when taken with potassium chloride. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with potassium chloride include:

  • aliskiren
  • angiotensin II receptor blockers, such as captopril or enalapril
  • anticholinergics such as benztropine
  • drospirenone
  • intraconazole or ketoconazole
  • glycopyrrolate
  • heparin
  • nicorandil
  • potassium sparing diuretics, such as spironolactone.

Note that this list is not all-inclusive and includes only common medications that may interact with potassium chloride. You should refer to the prescribing information for potassium chloride for a complete list of interactions.


Potassium chloride. Revised 11/2019.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use potassium chloride only for the indication prescribed.

Copyright 1996-2020 Revision date: December 28, 2019.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.