creatinine (serum)
Kidney FunctionBlood sampleResults Same dayNo fasting
Creatinine (Serum)
Creatinine is a waste product from normal muscle activity that your kidneys filter out. This test is a key marker of kidney function and overall kidney health.
Sample
Blood
Results
Same day
Fasting
Not required
Follow-up
Optional add-on
What this test detects
Creatinine
Kinetic spectrophotometry · serum
Quantitative · mg/dL
When to get this test
Kidney function
A core test for assessing how well the kidneys are filtering waste from the blood.
Estimating kidney filtration
Used to help estimate the glomerular filtration rate (eGFR), a measure of kidney performance.
Monitoring kidney conditions
Helps track kidney health over time, especially in people with risk factors.
How to prepare
01
No special preparation needed.
Common questions
What does creatinine tell me about my kidneys?
Creatinine builds up when the kidneys aren't filtering well, so higher levels can signal reduced kidney function. It's a widely used marker of kidney health.
Does muscle mass affect creatinine?
Yes, people with more muscle tend to have higher creatinine, while those with less may have lower levels. This is considered when interpreting results.