Creatinine
- Sample Type
- Standard
- Fasting
- No
- Unit
- mg/dL
Creatinine is a waste product produced by the muscles from the breakdown of a compound called creatine. It is filtered out of the blood by the kidneys and excreted in urine. Measuring serum creatinine is a critical component of the Basic Kidney Profile as it is used to estimate the Glomerular Filtration Rate (eGFR). It serves as a primary marker for kidney function; however, it is influenced by muscle mass, age, and sex.
Check Your Result
Check Your Result
Enter your lab result to see where you stand compared to the standard reference range.
Why Context Matters
Creatinine levels can be falsely elevated by high protein intake, creatine supplementation, or high muscle mass (athletes), leading to an underestimation of kidney function. Conversely, in elderly or malnourished patients, creatinine may appear 'normal' despite significant renal impairment due to low muscle mass.
Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.
Clinical References
Source-of-truth databases and clinical guidelines for Creatinine:
Official Sources
- Creatinine test - Mayo ClinicMayo Clinic
- Creatinine Test: MedlinePlus Medical TestMedlinePlus
Research & Guidelines
- PubMed: Creatinine Clinical GuidelinesNCBI / PubMed
Related Indicators
Medically Reviewed by Dr. Binoy Babu, MBBS
Board Certified Doctor • 10+ Years Clinical Experience
Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.
Get Notified When Dr. Babu Is Available