Creatinine
Creatinine is a waste product of muscle metabolism that the kidneys clear. It is the basis for assessing kidney function, and it also depends on muscle mass.
At a glance
- Sample
- Blood
- Units
- mg/dL (US), µmol/L (Europe)
- Often looked at with
- eGFR, Urea, Urea nitrogen (BUN), Uric acid
- Preparation
- No special preparation is usually needed. Sometimes you are asked not to eat meat for a day: it raises creatinine for a while. If other blood tests are done at the same time, you may be asked to come fasting.
Units: mg/dL and µmol/L
US labs usually print creatinine in mg/dL, most European labs in µmol/L. To convert, multiply mg/dL by 88.402.
µmol/L = mg/dL × 88.402 · molar mass 113.12 g/mol
This converter changes units only. It doesn’t tell you whether a number is in or out of any range: that depends on the range printed by your own lab, and on your doctor. Soma does not diagnose and is not medical advice.
Why lab ranges differ
Each lab sets its reference range for its own method and analyser, and many ranges differ by age and sex. Two labs can print different ranges for the same blood, so a result is read against the range on its own report, not against a number from another lab or a website.
Soma charts every creatinine result against the range printed by the lab that measured it.
What can affect the result
- A lot of meat the day before raises it.
- Intense exercise the day before.
- Creatine in sports supplements.
If something like this applies, mention it to the doctor who reads your results.
Questions
How do I convert creatinine from mg/dL to µmol/L?
Multiply mg/dL by 88.402. For example, 1 mg/dL is 88.4 µmol/L.
Why does my lab’s creatinine range differ from another lab’s?
Each lab sets its range for its own method and equipment, and many ranges differ by age and sex. That’s why a result is best read against the range printed on the same report.
How do I prepare for a creatinine test?
No special preparation is usually needed. Sometimes you are asked not to eat meat for a day: it raises creatinine for a while. If other blood tests are done at the same time, you may be asked to come fasting. Follow your lab’s instructions.
Related tests
Got a lab report with Creatinine?
Share it to Soma: it reads every row on your phone, with no account and no upload, and puts your creatinine on one chart with your earlier results, each against the range your lab printed.
Sources
- Creatinine Test — MedlinePlus, U.S. National Library of Medicine.
- Units: PubChem: Creatinine (creatinine), molar mass 113.12 g/mol, as the Soma app converts.
Mention of a source doesn’t mean it endorses Soma. This page explains the test; it doesn’t diagnose and is not medical advice. Talk to your doctor about what your results mean.