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Micro-K Side Effects

Generic name: potassium chloride

Medically reviewed by Last updated on Apr 27, 2024.

Note: This document contains side effect information about potassium chloride. Some dosage forms listed on this page may not apply to the brand name Micro-K.

Applies to potassium chloride: oral tablet extended release. Other dosage forms:

Serious side effects of Micro-K

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Other side effects of Micro-K

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

For Healthcare Professionals

Applies to potassium chloride: compounding powder, intravenous solution, oral capsule extended release, oral granule extended release, oral liquid, oral powder for reconstitution, oral tablet, oral tablet extended release.


Frequency not reported: Hyperkalemia (including cardiac arrest as a manifestation), hypervolemia, hyponatremia and hyponatremic encephalopathy, hypokalemia[Ref]

Hyperkalemia can cause muscle weakness, paresthesia of the extremities, listlessness, mental confusion, flaccid paralysis, cold skin, grey pallor, peripheral vascular collapse, fall in blood pressure, paralysis, cardiac arrhythmias, and heart block. Electrocardiogram abnormalities include disappearance of the P-wave, widening and slurring of QRS complex, changes of the S-T segment, tall peaked T-waves. At extremely high concentrations (8 to 11 mmol/L) may cause death from cardiac depression, arrhythmias, or arrest.[Ref]


Frequency not reported: Nausea, vomiting, flatulence, abdominal pain/discomfort, diarrhea, obstruction, bleeding, ulceration, perforation, gastrointestinal hemorrhage, local irritation of the mucosa

Postmarketing reports: Delayed intestinal transit[Ref]


Frequency not reported: Injection site pain, injection site phlebitis, infection at injection site, venous thrombosis extending from site of injection, extravasation[Ref]


Frequency not reported: Cardiac arrhythmias, cardiac arrest[Ref]


Rare (less than 0.1%): Skin rash

Frequency not reported: Urticaria, pruritus[Ref]


Frequency not reported: Febrile response[Ref]

Frequently asked questions


1. Cerner Multum, Inc. "UK Summary of Product Characteristics."

2. Cerner Multum, Inc. "Australian Product Information."

3. (2016) "Product Information. Klor-Con M10 (potassium chloride)." Upsher-Smith Laboratories Inc

4. (2016) "Product Information. Potassium Chloride (potassium chloride)." Pharmaceutical Assoc Inc Div Beach Products

5. "Product Information. Potassium Chloride In Dextrose and S (LVP solution with potassium)." B Braun Medical Inc, Irvine, CA.

Further information

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

Some side effects may not be reported. You may report them to the FDA.