⚖️ Electrolytes & Minerals

Potassium: What It Means for Your Health

Potassium is the primary intracellular electrolyte and is critical for maintaining normal heart rhythm, muscle contraction, and nerve function. The body maintains potassium within a very narrow range because both high and low levels can cause life-threatening cardiac arrhythmias. Kidneys are the main regulators of potassium balance. Potassium levels must always be interpreted alongside kidney function.

Full Name
Serum Potassium (K+)
Normal Range
3.5–5 mEq/L
Also Known As
K, K+

Reference Range

LowNormal: 3.5–5 mEq/LHigh

Reference ranges may vary between laboratories, age groups, and sexes. The values shown are general adult reference ranges. Always compare your results to the specific range provided by your testing laboratory.

What Is Potassium?

Potassium is the primary intracellular electrolyte and is critical for maintaining normal heart rhythm, muscle contraction, and nerve function. The body maintains potassium within a very narrow range because both high and low levels can cause life-threatening cardiac arrhythmias. Kidneys are the main regulators of potassium balance. Potassium levels must always be interpreted alongside kidney function.

Commonly included in:

Basic Metabolic Panel (BMP)Electrolyte PanelComprehensive Metabolic Panel

What Does High Potassium Mean?

Above 5 mEq/L

Elevated potassium (hyperkalemia, above 5.0 mEq/L) can cause dangerous heart rhythm disturbances. Causes include kidney disease, ACE inhibitors/ARBs, potassium-sparing diuretics, acidosis, cell destruction (rhabdomyolysis, hemolysis, burns), and excessive potassium supplements. Severe hyperkalemia (above 6.5) is a cardiac emergency requiring immediate treatment.

What Does Low Potassium Mean?

Below 3.5 mEq/L

Low potassium (hypokalemia, below 3.5 mEq/L) can cause muscle weakness, cramps, fatigue, constipation, and cardiac arrhythmias. Common causes include diuretics, vomiting, diarrhea, excessive sweating, low dietary intake, and certain kidney diseases. Severe hypokalemia (below 2.5) is life-threatening.

Related Biomarkers in Electrolytes & Minerals

Sodium
Key electrolyte that regulates fluid balance, blood pressure, and nerve function.
Range: 136–145 mEq/L
Calcium
Essential mineral for bones, teeth, muscle contraction, and nerve function.
Range: 8.5–10.5 mg/dL
Magnesium
Essential mineral involved in over 300 enzymatic reactions in the body.
Range: 1.7–2.2 mg/dL
Phosphorus
Mineral important for bones, teeth, energy production, and DNA.
Range: 2.5–4.5 mg/dL
Zinc
Essential trace mineral for immune function, wound healing, and taste/smell.
Range: 60–120 ug/dL

Track Your Potassium Over Time

Upload your blood test results to Hemoly and see how your Potassium levels change over time. Get trend analysis, educational insights, and a personal health timeline.

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Medical Disclaimer

This information is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Reference ranges may vary between laboratories. Always consult a qualified healthcare professional for interpretation of your blood test results and before making any health decisions.