Creatinine (CR)

Waste product of muscle metabolism, cleared by kidneys. Used to estimate eGFR.

Units

mg/dL

Reference (Male)

0.74 – 1.35 mg/dL

Reference (Female)

0.59 – 1.04 mg/dL

Aliases

Serum creatinine

What it measures

Waste product of muscle metabolism, cleared by kidneys. Used to estimate eGFR.

What a high value can mean

Reduced kidney function, dehydration, high-protein diet, muscle injury, certain meds (NSAIDs, ACE-i).

What a low value can mean

Low muscle mass, pregnancy, severe liver disease.

Conditions it helps assess

Kidney function
Muscle mass

Reading these numbers in context

Reference ranges describe the central 95 % of a healthy reference population — 5 % of perfectly healthy people fall outside any given range by definition. A single mildly abnormal value is rarely meaningful on its own. blood-test.life always interprets values together with related biomarkers before flagging.

Related biomarkers in Kidney Panel

Estimated GFR eGFR Calculated kidney filtration rate. Defines chronic kidney disease (CKD) stage. Blood Urea Nitrogen BUN Nitrogen waste from protein breakdown. BUN/creatinine ratio helps differentiate causes of kidney injury.