Skip to content

Serum or Plasma Creatinine Concentration (Standard Method)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of creatinine, a waste product from muscle metabolism, in your blood or plasma. It helps assess how well your kidneys are filtering blood.

Quick summary

["A creatinine test helps check kidney function by measuring waste product levels in your blood."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
105033-5
Short code
ISAba1 upstream blaOXA-51 Islt/Spm Ql
Synonyms
ISAba1 upstream blaOXA-51 Islt/Spm Ql
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
molgen
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Your Kidneys Matter

Kidneys are vital organs that filter waste and excess substances from your blood, including creatinine. When kidneys don’t work well, creatinine levels can rise, indicating potential kidney damage or disease.

What This Test Reveals

Elevated creatinine levels may suggest reduced kidney function, while normal levels generally indicate healthy filtering. However, other factors like muscle mass or hydration status can also affect results.

How the Test Works

A small blood sample is drawn to measure creatinine concentration using standard laboratory methods. This helps doctors compare your results to expected ranges for your age, sex, and health status.

Common Reasons for Testing

Doctors may order a creatinine test to monitor kidney health before or after treatments, diagnose kidney disease, or check for conditions like diabetes or heart disease that affect kidney function.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Creatinine

Frequently asked questions

What does a high creatinine level mean?
A high creatinine level may indicate poor kidney function, but it’s not always definitive. Other conditions, like dehydration or muscle disorders, can also influence results. Your doctor will consider your overall health and other test results to interpret the meaning.
What does a low creatinine level mean?
Low creatinine levels might suggest kidney disease (if creatinine should normally be higher) or conditions that reduce muscle mass. Your doctor will review your medical history and other test results to understand the cause.
How often should I get this test?
Your doctor will determine how often you need this test based on your health condition, treatment plan, or risk factors. Regular monitoring may be needed if you have kidney disease, diabetes, or other chronic conditions affecting kidney function.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy