Is high creatinine always a sign of kidney problems?

Not necessarily. Creatinine may be temporarily elevated due to dehydration, heavy protein intake, or recent intense exercise. Persistent elevation may warrant further evaluation.

How is creatinine used to estimate kidney function?

Creatinine is used together with age, sex, and body size to estimate the glomerular filtration rate (eGFR), which is a common indicator of kidney function.

High Creatinine Levels: What They May Mean

An overview of what creatinine measures, common reasons it may be elevated, and what next steps your clinician might consider.

Creatinine is a waste product produced by normal muscle activity. It is filtered out of the blood by the kidneys and excreted in urine, which is why serum creatinine is widely used as a marker of kidney function.

Typical reference range

Reference ranges may differ between laboratories. As a general adult guide:

Male: 0.74–1.35 mg/dL
Female: 0.59–1.04 mg/dL

Reasons creatinine may be elevated

A higher-than-expected creatinine value does not, by itself, confirm any specific condition. It may be associated with:

Reduced kidney filtration
Dehydration
High dietary protein or creatine supplementation
Strenuous exercise in the days before the test
Certain medications

What clinicians may consider next

If creatinine is elevated, your clinician may look at the eGFR, urine albumin, electrolytes, and your medical history. A repeat test may be ordered to confirm the trend before any conclusions are drawn.

When to seek advice

A single moderately elevated value is rarely an emergency, but persistent elevation or values significantly above the range may warrant prompt review with a qualified clinician.