Test Overview

Test Methodology

Screen: Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS), Confirmation: Gas Chromatography/Mass Spectrometry (GC/MS)

Test Usage

Detection of gamma hydroxy butyrate in urine.

Reference Range*

Negative (screening threshold 5 mcg/mL).

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

The expected detection period (dose-dependent) is 3 - 10 hours.

Test Details

Days Test Performed


Analytic Time

7 - 9 days

Soft Order Code




Gamma Hydroxybutyric Acid
Gamma OH-butyrate
Date Rape Drug
Drug Screen, Gamma Hydroxy Butyrate
Gamma-Hydroxybutyric Acid (GHB)

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Laboratory Reference

Mayo FGHSU (58036) (MedTox 19255)

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Specimen Requirements

Offsite Collection Instructions

Collect random urine specimen and refrigerate.

Normal Volume

10 mL urine

Minimum Volume

1.5 mL urine

Additional Information

If the GHB Screen is non-negative, GHB Confirmation (FGHAC) will be performed at an additional charge. By ordering this test the clinician acknowledges that additional reflex testing will be performed and billed at a separate additional charge if indicated. Test sent to Mayo Medical Laboratories; performed by MedTox Laboratories.

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