Indicator Explainer
Creatinine
The breakdown product of creatine, a constituent of muscle tissue, that is excreted by the kidney and whose serum level is used to evaluate kidney function.
This page explains what the indicator is and how results are interpreted in general terms. Reference ranges depend on the laboratory, the method, and your own situation — no single “normal value” applies to everyone. This page is health information, not a diagnosis. For symptoms, treatment, or urgent concerns, contact a healthcare professional.
When it is tested
Source: National Cancer Institute, NCI Thesaurus 26.09d, C399. NCI definition, reproduced without modification under CC BY 4.0. Source identity and definition checked automatically on 2026-10-18. No individual clinical interpretation or human reviewer is asserted.
Reading results
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also Known As
References
- NCI Thesaurus 26.09d — Creatinine (C399)
- Source: National Cancer Institute, NCI Thesaurus 26.09d, C399. NCI definition, reproduced without modification under CC BY 4.0.
- Within-Patient Association Between Creatinine Clearance and Serum Lithium Concentrations During Routine Monitoring. — J Clin Psychopharmacol, 2026-10-09 (PMID 42847418; literature)
- Cystatin C Based eGFR Identifies Clinically Significant Acute Kidney Injury Missed by Serum Creatinine in Pediatric Transplant-Associated Thrombotic Microangiopathy. — Transplant Cell Ther, 2026-10-08 (PMID 42849880; literature)
- Heavy Numbers: When Obesity Tips the Balance between Creatinine- and Cystatin C-Based eGFR. — Kidney360, 2026-10-08 (PMID 42848598; literature)