Serum or Plasma Creatinine Concentration (Qualitative or Quantitative Measurement)
This test measures the amount of creatinine, a waste product from muscle metabolism, in your blood or plasma. It helps assess how well your kidneys are filtering blood.
["A creatinine test helps check kidney function by evaluating how well your kidneys remove waste from your blood."]
Key facts at a glance
- LOINC
- 71890-8
- Short code
- COHgb MFr.DF Bld
- Synonyms
- COHgb MFr.DF Bld
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- 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 This Test Is Done
Your healthcare provider may order a creatinine test to monitor kidney health, especially if you have symptoms like swelling, fatigue, or changes in urine output. It’s also used before certain procedures, during pregnancy, or when managing conditions like high blood pressure or diabetes.
What to Expect During the Test
A blood sample is taken from a vein in your arm. You may feel a small pinch, but it usually doesn’t cause discomfort. If you’re tested for plasma, your provider may use an anticoagulant to prevent clotting. The test itself is quick and painless.
Preparation and Timing
No special preparation is needed unless instructed by your provider. For some conditions, you might be asked to fast or avoid certain medications. Results are typically available within 24–48 hours, depending on your lab.
How Results Are Interpreted
Results are compared to a reference range specific to your lab, which accounts for factors like age, sex, and overall health. High levels may signal kidney problems, while very low levels could indicate muscle disorders or errors in measurement.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/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.
Creatinine levels are a key indicator of kidney function. Elevated levels suggest impaired filtration, which may require further testing or adjustments to medications. Low levels might prompt additional evaluation for conditions like malnutrition or liver disease.
Short name
Creatinine Level (Serum/Plasma)
Frequently asked questions
What causes creatinine levels to be high?
What if my creatinine level is outside the normal range?
Can diet affect creatinine levels?
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