What it is used for
- Treating and preventing low potassium levels (hypokalaemia)
- Replacing potassium lost through certain water pills, vomiting or diarrhoea
- Supporting people whose medicines or conditions lower potassium, when prescribed
How it works
Potassium is an essential electrolyte needed for normal heart rhythm, muscle contraction and nerve signals. When levels fall too low, the heart and muscles can be affected, so replacing potassium restores normal function.
How it is taken
Available as modified-release tablets, effervescent or soluble tablets, and liquids; it is also given as a carefully controlled infusion in hospital. Oral forms are usually taken with food and a full glass of water to protect the stomach. Take it exactly as your doctor or pharmacist directs, as potassium balance is closely monitored.
No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.
Common side effects
- Stomach upset, nausea or diarrhoea
- Wind or bloating
- Throat or stomach irritation if not taken with enough water
Serious effects — get help
- Signs of high potassium: muscle weakness, numbness or tingling, slow or irregular heartbeat
- Severe stomach pain, vomiting blood or black stools (possible ulcer or bleeding)
- Difficulty swallowing or chest pain when taking tablets
If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.
Interactions to watch
- Potassium-sparing water pills and certain blood pressure medicines (ACE inhibitors, ARBs), which raise potassium
- Salt substitutes that contain potassium
- Some other medicines that affect potassium levels
Who should take care
- Only take potassium supplements when prescribed and monitored, as both high and low levels are dangerous
- Tell your clinician if you have kidney disease or take blood pressure medicines that affect potassium
- Take tablets with plenty of water and do not crush modified-release forms unless told to
- Avoid potassium-containing salt substitutes unless your clinician approves