Creatinine is a blood test that measures creatinine levels in the blood. Normal range: Creatinine is typically about 60-110 μmol/L in men and 45-90 μmol/L in women, the difference reflecting muscle mass. Because it depends on muscle, labs also report an eGFR (estimated glomerular filtration rate) calculated from creatinine, age and sex, which is the better measure of actual kidney function.. It is commonly used to the most reliable single marker for kidney function assessment..
What is Creatinine?
A waste product produced by muscles and filtered by the kidneys.
Why is it measured?
The most reliable single marker for kidney function assessment.
Normal Reference Range
Creatinine is typically about 60-110 μmol/L in men and 45-90 μmol/L in women, the difference reflecting muscle mass. Because it depends on muscle, labs also report an eGFR (estimated glomerular filtration rate) calculated from creatinine, age and sex, which is the better measure of actual kidney function.
Note: Reference ranges may vary between laboratories. Always consult your healthcare provider for interpretation.
What Causes High CREATININE?
High creatinine usually indicates reduced kidney filtration — acute kidney injury (often from dehydration, low blood pressure or nephrotoxic drugs) or chronic kidney disease. Non-kidney causes that raise it without true impairment include large muscle mass, a very high meat intake before the test, intense exercise, and muscle breakdown (rhabdomyolysis). Some medications block creatinine secretion and nudge it up without harming the kidney.
What Causes Low CREATININE?
Low creatinine reflects low muscle mass rather than a problem and is seen with ageing, frailty, malnutrition, and conditions causing muscle wasting. It also falls in pregnancy because kidney filtration increases. A low value can cause eGFR to overestimate kidney function in frail people.
How Often Should CREATININE Be Tested?
Creatinine (with eGFR) is part of the routine UEC panel and is one of the most frequently measured tests. It is checked at health assessments and monitored regularly in chronic kidney disease, diabetes, high blood pressure, and before and during treatment with drugs cleared by or toxic to the kidneys.
Related Blood Markers
Creatinine is interpreted with eGFR and urea (the urea:creatinine ratio separates dehydration from intrinsic kidney disease), the electrolytes, and the urine albumin-to-creatinine ratio (ACR) for early kidney damage.
Key Facts
- •Category: Vital Organ Functions
- •Unit of Measurement: μmol/L
- •Test Code: CREATININE
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