Serum Potassium Concentration (Mass Concentration)
This test measures the amount of potassium, an essential electrolyte, in your blood serum. Potassium helps regulate heart rhythm, muscle function, and fluid balance.
["Potassium levels can affect heart health and muscle function."]
Key facts at a glance
- LOINC
- 88459-3
- Short code
- SRA 1.0 IU/mL LMW heparin Ser-aCnc
- Synonyms
- SRA 1.0 IU/mL LMW heparin Ser-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 17
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order this test to check for low or high potassium levels, which can occur due to conditions like kidney problems, heart disease, or certain medications. It may also be done before surgery, during pregnancy, or if you have symptoms like muscle weakness, irregular heartbeat, or nausea.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it’s part of a broader metabolic panel. Bring any medications you’re taking to your appointment.
How the Test Is Performed
A healthcare provider will draw blood from a vein in your arm using a small needle. You may feel a slight sting, but it usually doesn’t cause pain. The blood sample is then sent to a lab for analysis.
What the Results Mean
Results are typically reported in milliequivalents per liter (mEq/L). Low potassium (hypokalemia) or high potassium (hyperkalemia) can signal underlying health issues, so discuss any changes with your doctor.
Reference range
NCBI: NSE 0-17 ng/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Potassium Level
Frequently asked questions
Potassium is critical for nerve and muscle function, including the heart. Abnormal levels can cause serious complications like arrhythmias, muscle cramps, or even heart failure. Your doctor may monitor potassium closely if you have conditions like kidney disease, diabetes, or take diuretics.
What causes potassium levels to be too low or too high?
How long does it take to get results?
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 17, 2026. · Read our editorial policy