What the label lists and what reports show
Potassium chloride side effects
Potassium chloride's FDA label: “The most common adverse reactions to oral potassium salts are nausea, vomiting, flatulence, abdominal pain/discomfort, and diarrhea.” FAERS holds 113,262 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is diarrhoea (8,243 reports).
- Generic listed
- A presentation discontinued
Check it at the source: the potassium chloride FDA label on DailyMed (effective July 14, 2025, Upsher-Smith Laboratories, LLC); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse reactions to oral potassium salts are nausea, vomiting, flatulence, abdominal pain/discomfort, and diarrhea.
From the label: adverse reactions, continuedOne of the most severe adverse effects is hyperkalemia [see CONTRAINDICATIONS , WARNINGS and OVERDOSAGE ]. There have also been reports of upper and lower gastrointestinal conditions including obstruction, bleeding, ulceration, and perforation [see CONTRAINDICATIONS and WARNINGS ]. The most common adverse reactions to oral potassium salts are nausea, vomiting, flatulence, abdominal pain/discomfort, and diarrhea. These symptoms are due to irritation of the gastrointestinal tract and are best managed by diluting the preparation further, taking the dose with meals or reducing the amount taken at one time.
Source: FDA drug label, Upsher-Smith Laboratories, LLC, effective July 14, 2025 (SPL set b89910f6-4ff5-4a62-8269-696f7c10e4f6), via openFDA; the full label on DailyMed
What do FAERS reports show?
113,262 reports list potassium chloride among the medicines taken, each a report of something that happened, not proof the medicine caused it; 15,936 are coded as a death and 49,964 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 22 reactions below, 3 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Potassium chloride: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions