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Creatinine Clearance (from 24-hour urine collection)

Published: August 9, 2026Updated: August 17, 2026

This test measures how well your kidneys filter waste products, using a 24-hour urine sample. It helps assess kidney function and blood flow to the kidneys.

Quick summary

["A clear picture of kidney health through urine waste clearance over a full day."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
16688-4
Short code
CK Fld-cCnc
Synonyms
CK Fld-cCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
22
Ref high
198
Critical range
— – 10000 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82553
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 This Test Matters

Creatinine clearance is a key indicator of kidney function because it reflects how efficiently your kidneys remove waste from your blood. Unlike a single blood test, this method provides a more comprehensive view over a full day’s filtration process.

How the Test Works

Your doctor will collect all urine produced in a 24-hour period. The urine is tested for creatinine levels, while blood creatinine and volume are also measured. The test calculates how much creatinine is cleared from your blood over time.

Preparation

No special preparation is needed, but you should drink enough fluids to produce urine throughout the day. Avoid using diuretics or medications that affect kidney function without consulting your doctor.

What to Expect

You’ll need to collect every drop of urine for 24 hours, including at night. A urine collection kit will be provided, and you’ll return the sample to the lab. Blood tests may also be done on the same day for comparison.

Reference range

Adult males: 22-198 U/L; Females: 22-198 U/LN/A

Specimen: serum

No special preparation required. Inform provider of any chest pain or symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

24-Hour Urine Creatinine Clearance

Frequently asked questions

How is creatinine clearance different from a blood creatinine test?
Creatinine clearance measures how well your kidneys filter waste from urine over a full day, while blood creatinine tests measure the waste level in your blood at a single point in time. Clearance provides a more accurate long-term view of kidney function.
Can I take medications that affect urine production before this test?
No, avoid diuretics or medications that alter urine output without consulting your doctor. Some medications can affect kidney function, so always check with your healthcare provider first.
What if I miss collecting urine for part of the day?
If you miss urine collection, you’ll need to restart the process. Your doctor may adjust the test timing or use alternative methods if necessary, such as a blood test alone for an estimate.
  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 17, 2026. · Read our editorial policy