A single high potassium result can be a lab fluke or a serious medical problem. Know the common causes, how to tell when it’s urgent, and clear steps you can take right away. This page gives practical advice you can use if you (or someone you care for) get a high potassium reading.
Potassium levels rise when the body can’t remove it or when it moves out of cells into the blood. Common causes include: reduced kidney function, potassium-sparing drugs (spironolactone, amiloride, triamterene), ACE inhibitors or ARBs, high-dose NSAIDs, excess supplements or salt substitutes (potassium chloride), tissue breakdown (crush injury, rhabdomyolysis), and untreated diabetic ketoacidosis. Sometimes the lab result is false — called pseudohyperkalemia — due to hemolysis in the blood sample, prolonged tourniquet use, or very high white cell or platelet counts.
Medications are a major trigger. If you start an ACE inhibitor, ARB, or a potassium-sparing diuretic and then see rising potassium, call your provider. Also watch for combination effects: two drugs that both raise potassium multiply the risk.
Symptoms can be subtle: muscle weakness, numbness or tingling, fatigue, or palpitations. Severe hyperkalemia can cause life‑threatening heart rhythm changes — think peaked T waves, widening of the QRS on ECG, or sudden palpitations. If you have chest pain, severe weakness, fainting, or sudden palpitations, go to the emergency room right away.
If your lab shows high potassium but you feel fine: 1) Ask for a repeat blood draw to rule out pseudohyperkalemia. 2) Stop potassium supplements and salt substitutes until you talk to your clinician. 3) Check recent meds and share the list with your doctor or pharmacist. Don’t make big diet changes without guidance — if your kidneys are fine, mild dietary limits may not be needed.
Treatment in the clinic or ER depends on level and ECG. Immediate measures can include IV calcium (stabilizes the heart), IV insulin with glucose (moves potassium into cells), nebulized albuterol, IV sodium bicarbonate if acidotic, diuretics like furosemide if urine output is OK, or potassium-binding drugs such as patiromer or sodium zirconium cyclosilicate. If kidneys aren’t working or levels stay dangerously high, dialysis removes potassium fast.
Prevention is simple: get baseline and follow-up blood tests when starting drugs that affect potassium, avoid unnecessary potassium supplements and salt substitutes, and keep your provider updated about new prescriptions. If you have chronic kidney disease, ask how often to check potassium and what foods to limit.
Questions about a recent lab result? Contact your clinic, repeat the test if advised, and bring a current medication list. Quick action can prevent complications and might save you a trip to the ER.
A real-deal look at the hidden health risks when folks mix alcohol with potassium-sparing diuretics like spironolactone—spotlighting hyperkalemia and its dangers.
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