Skip to content

Serum Creatinine Concentration (Mass Concentration)

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

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

Quick summary

["Kidney function is evaluated by checking creatinine levels—higher values may indicate kidney issues."]

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

Key facts at a glance

LOINC
31493-0
Short code
LCMV IgG Ser-aCnc
Synonyms
LCMV IgG Ser-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82784
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

Your kidneys filter waste and excess substances from your blood, including creatinine. This test helps doctors check if your kidneys are working properly by measuring how much creatinine stays in your blood.

What Creatinine Does in Your Body

Creatinine is a byproduct of muscle metabolism. When your kidneys filter it out of your blood, they remove it from your body through urine. If your kidneys aren’t working well, creatinine builds up in your blood.

How This Test Works

A small blood sample is taken and sent to a lab. The lab uses an automated test to measure creatinine levels, often through a method like enzymatic analysis or chemiluminescence.

What Normal Results Mean

While exact reference ranges vary by lab, higher creatinine levels may suggest reduced kidney function. Lower levels might indicate overhydration or other conditions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Creatinine Level

Frequently asked questions

What could cause elevated creatinine?
Elevated creatinine levels may signal kidney disease, dehydration, or conditions affecting muscle mass. It can also be influenced by medications, high protein intake, or severe illness.
What could cause low creatinine?
Low creatinine levels might suggest overhydration, muscle wasting, or liver disease, which can affect muscle breakdown. Rarely, it could indicate lab error or very low muscle mass.
How often should I get this test?
Your doctor may order this test periodically if you have kidney-related conditions, high blood pressure, diabetes, or other risk factors. Follow their guidance for timing.
  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