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Gamma-Hydroxybutyrate (GHB) and Creatinine, Urine — Toxicology Screen

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

A urine toxicology test that detects GHB, a central nervous system depressant sometimes misused as a club drug, and may include creatinine to assess urine concentration.

Quick summary

["Detectable GHB in urine may indicate recent exposure, but screening results should be confirmed when clinically important."]

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

Key facts at a glance

LOINC
80158-9
Short code
Gal-Hyl/Creat Ur-sRto
Synonyms
Gal-Hyl/Creat Ur-sRto
Category
kidney
Sample
urine
Container
Sterile urine container
Units
N/A
Ref low
1.5
Ref high
9
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
83002
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

This test measures gamma-hydroxybutyrate (GHB) in urine. Creatinine may also be reported to help account for how concentrated the urine sample is.

Why might I need this test?

Urine GHB testing may be ordered when there is concern about recent GHB use, particularly in medical, toxicology, or substance-use evaluations. It may be part of a broader drug screen.

How is the test performed?

A urine sample is collected and analyzed in the laboratory. Because screening tests can sometimes be misleading, an unexpected result may require a more specific confirmatory test.

How do I prepare for the test?

Follow your clinician's instructions about when and how to collect the urine sample. Collection timing can be important because GHB may be detected only for a limited period after use.

Reference range

Follicular: 1.5-9.0 mIU/mLN/A

Specimen: urine

For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Detectable GHB in urine may indicate recent exposure, but collection time, urine concentration, and laboratory methods affect interpretation. Creatinine can help determine whether the sample is very dilute or concentrated. A screening result should be considered together with the clinical situation and, when needed, confirmatory testing.

Short name

Urine GHB screen

Frequently asked questions

What does a positive urine GHB result mean?
It may indicate recent GHB exposure, but the result should be interpreted with other clinical and laboratory information. Confirmation may be needed.
How soon after use can GHB be detected in urine?
Detection depends on the amount used, individual metabolism, urine concentration, and the laboratory method. Testing too long after exposure may produce a negative result.
Why is creatinine included with the GHB test?
Creatinine reflects urine concentration, which can affect how an analyte result is interpreted. It is commonly used as a comparison when evaluating a drug in urine.
  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