What could be causing my hyperkalemia (elevated potassium level)?

Evaluation of Your Hyperkalemia (Potassium 5.8 mmol/L)

Your potassium level of 5.8 mmol/L requires prompt evaluation and intervention, as levels >5.5 mmol/L are associated with increased mortality risk and cardiac complications, particularly if you have underlying heart failure, chronic kidney disease, or diabetes. 1, 2

Immediate Assessment Needed

Get an ECG immediately to assess for cardiac toxicity, as hyperkalemia can cause life-threatening arrhythmias even without symptoms. 3 ECG changes progress from peaked T waves to flattened P waves, prolonged PR interval, widened QRS, and potentially cardiac arrest. 3

Verify the result with a repeat blood test to rule out pseudohyperkalemia from hemolysis during blood collection—this is a common false elevation. 3 Request that the lab handle the sample carefully to avoid squeezing the tourniquet too long or excessive fist clenching during the draw. 4

Critical Information You Need to Provide

Medications You're Taking

• ACE inhibitors (lisinopril, enalapril, ramipril) 5
• ARBs (losartan, valsartan, irbesartan) 5
• Aldosterone antagonists (spironolactone, eplerenone) 5
• NSAIDs (ibuprofen, naproxen, even if occasional use) 5
• Potassium-sparing diuretics (amiloride, triamterene) 5
• Beta-blockers (metoprolol, atenolol, carvedilol) 5
• Trimethoprim (in Bactrim/Septra) 5
• Heparin or low-molecular-weight heparin 5
• Herbal supplements (alfalfa, dandelion, horsetail, nettle) 3
• Salt substitutes (these contain potassium chloride instead of sodium) 3

Medical Conditions to Disclose

• Kidney function: Do you know your creatinine or eGFR? Hyperkalemia commonly occurs when kidney function declines below 30 mL/min/1.73m². 6, 7
• Diabetes mellitus: This significantly increases your risk of hyperkalemia-related complications. 1, 2
• Heart failure: Even mild heart failure increases mortality risk at your potassium level. 1, 2
• Recent illness: Dehydration, vomiting, diarrhea, or reduced oral intake can concentrate potassium. 4
• Muscle breakdown: Recent intense exercise, trauma, or muscle injury releases intracellular potassium. 7
• Blood sugar control: Uncontrolled hyperglycemia can shift potassium out of cells. 4

Dietary Factors to Consider

• High-potassium foods consumed recently: bananas, oranges, potatoes, tomato products, avocados, spinach, beans, yogurt, chocolate, nuts. 1, 3
• Use of salt substitutes (Morton Salt Substitute, Nu-Salt, etc.) which are pure potassium chloride. 3
• Recent dietary changes or increased consumption of "healthy" foods that happen to be potassium-rich. 1

Most Likely Causes in Your Situation

Given you've excluded liver disease, Addison's disease, and known potassium supplements, the most common causes are:

1. Medication-induced (accounts for 50% of hyperkalemia cases): Particularly RAAS inhibitors (ACE inhibitors/ARBs), NSAIDs, or their combination. 5, 8

2. Unrecognized kidney dysfunction: Even mild-to-moderate CKD (eGFR 30-60) can cause hyperkalemia, especially with certain medications. 6, 7

3. Dietary excess combined with reduced excretion: High potassium intake from diet or salt substitutes in the setting of borderline kidney function. 1, 3

4. Pseudohyperkalemia: Hemolysis during blood draw, prolonged tourniquet time, or excessive fist clenching. 3, 4

Immediate Actions Required

If you have any symptoms (muscle weakness, palpitations, chest discomfort, nausea), go to the emergency department immediately. 4, 7

If asymptomatic, contact your physician within 24-48 hours for: 2, 3

• Repeat potassium level (careful draw technique)
• ECG
• Comprehensive metabolic panel (kidney function, glucose, bicarbonate)
• Medication review
• Dietary assessment

Start dietary potassium restriction immediately to <3 g/day (77 mEq/day) by avoiding high-potassium foods and salt substitutes. 3 Presoaking root vegetables can lower potassium by 50-75%. 3

Common Pitfalls to Avoid

• Don't ignore this level: Even though 5.8 mmol/L isn't immediately life-threatening, levels >5.5 mmol/L are associated with increased mortality, and the optimal range is actually 3.5-5.0 mmol/L. 1, 2

• Don't assume it's just dietary: Medication effects and kidney dysfunction are far more common causes than diet alone. 5, 8

• Don't stop beneficial medications without guidance: If you're on ACE inhibitors or ARBs for heart or kidney protection, these shouldn't be stopped abruptly—dose adjustment or addition of potassium binders may allow continuation. 2, 3

• Don't delay follow-up: Persistently elevated potassium is associated with higher mortality risk, and normalization improves outcomes. 1