Potassium in Whole Blood (Concentration)
This test measures the amount of potassium, a vital mineral electrolyte, in your blood. Potassium helps regulate heart rhythm, muscle function, and fluid balance.
["Potassium levels help doctors assess heart health and check for conditions like low or high potassium."]
Key facts at a glance
- LOINC
- 32713-0
- Short code
- Potassium BldA-sCnc
- Synonyms
- Potassium BldA-sCnc
- Category
- electrolyte
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 3.5
- Ref high
- 5
- Critical range
- 2.5 N/A – 6.5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84132
- SNOMED
- 110742001
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order this test if you have symptoms like muscle weakness, irregular heartbeat, or signs of electrolyte imbalances. It’s also used to monitor kidney function, heart health, or after treatments like diuretics or certain medications that affect potassium levels.
What to Expect Before the Test
No special preparation is needed, but avoid eating or drinking anything (except water) for at least 8–12 hours before the test if instructed. Tell your doctor about any medications, supplements, or recent illnesses that might affect results.
What Happens During the Test?
A healthcare provider will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but it usually takes only a few seconds. The blood sample is then sent to a lab for analysis.
What the Results Mean
Results are compared to a reference range, but exact values can vary by lab. Low potassium (hypokalemia) may cause muscle cramps or fatigue, while high potassium (hyperkalemia) can affect heart rhythm. Your doctor will discuss results in relation to your symptoms and health.
Reference range
Adult: 3.5-5.0 mmol/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Potassium Level
Frequently asked questions
What Are Common Causes of Abnormal Results?
How Often Should I Get This Test?
Can I Avoid This Test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy