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Order Code MISMT - see under Specimen Required for more ordering info. Gamma-Hydroxybutyric Acid (GHB), Serum or Urine

Specimen Requirements

Fill out Medtox Requisition Toxicology and Therapeutic Drug Monitoring form; account number is 1669 (this should already be on the form).


Call MedTox courier at 651-628-6166 for specimen pick-up.


Collect 1 of the following specimens as close to suspected ingestion as possible:


Serum (MedTox test code#365)
Draw blood in a plain, red-top tube or dark green-top (heparin) tube. Spin down and send 5 mL of serum or heparinized plasma.


Urine (MedTox test code #1365)
10 mL from a random urine collection in a clean, plastic urine container with no preservative.

Performing Laboratory

MEDTOX Laboratories, Inc.

Day(s) Test Set Up

Monday through Sunday

Per MedTox, this test is available STAT for additional fee of $150 per test, but testing still may not be performed until next day.


Screen: Gas Chromatography/Flame Ionization Detection (GC-FID)

Confirmation: Gas Chromatography/Mass Spectrometry (GC/MS)

Specimen Transport Temperature

Ambient temperature is acceptable for shipping and/or short-term storage (up to 3 days); specimen may also be refrigerated or frozen

Reference Values


Test Classification and CPT Coding


82542-If positive