Creatinine

The primary marker of kidney filtration function.

What it is

Creatinine is a waste product of muscle metabolism, filtered by the kidneys at a relatively constant rate. Because production is fairly constant, blood creatinine levels reflect kidney filtration ability (GFR) more directly than urea.

Why it matters

Several chemotherapy agents are nephrotoxic (cisplatin being a major example). Monitoring creatinine through treatment cycles is essential — a rising creatinine signals kidney stress that may require dose adjustment or additional kidney protection protocols.

How to test

Standard renal function panel.

This information is for educational purposes only. Always discuss testing and interpretation of results with your care team.

Optimal range

Men: 62–115 µmol/L. Women: 53–97 µmol/L.

How often

Before each chemotherapy cycle.