Creatinine

also known as Cr

NORMAL_RANGE
0.7 – 1.3 mg/dL
UNIT
mg/dL

/WHAT_IT_IS

Creatinine is a muscle breakdown product cleared by the kidneys. It's the simplest kidney function marker, but heavily influenced by muscle mass.

/NORMAL_RANGE

Reference: 0.7–1.3 mg/dL. Higher in muscular men — don't panic at 1.3–1.5 if you're built.

What does high Cr mean?

  • +Kidney dysfunction, dehydration, high muscle mass, recent intense exercise, high protein meal, creatine supplementation.

What does low Cr mean?

  • +Low muscle mass, severe liver disease.

/ON_TRT

TRT increases muscle mass, which raises creatinine independently of kidney function. Use eGFR (which accounts for age/sex) rather than creatinine alone, and cystatin C if you want a truly muscle-independent kidney marker.

/RELATED

/TRACK_THIS

Track Cr in the app.

Upload your lab PDF — MyTRT extracts every marker with Gemini Vision. Charts, trends, and TRT-aware insights. Free on iOS and Android.

Last reviewed: 2026-06-04 · MyTRT does not provide medical advice. Always consult your physician.