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Barbituratesurmcnc

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

A urine test that detects the presence of barbiturate drugs in your system.

Quick summary

{"This test checks for barbiturate drugs (sedatives) in your urine","It is used for drug screening, monitoring treatment, or investigating overdose","Results indicate presence or absence, not the amount taken"}

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

Key facts at a glance

LOINC
9426-8
Short code
BARBU
Synonyms
Barbiturates Ur-mCnc
Category
chemistry
Sample
urine
Container
Sterile, leak-proof urine collection container with secure screw-cap lid; no preservative required for screening assays. For forensic/legal specimens, chain-of-custody container with tamper-evident seal is required.
Units
N/A
Ref low
200
Ref high
300
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
Immunoassay screening (e.g., EMIT, CEDIA, or FPIA) with confirmation by Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
CPT
80307
SNOMED
250649006
Specimen volume
30-50 mL (minimum 10 mL required for screening and confirmation testing)
Stability
Room temperature (15-25°C): up to 48 hours; Refrigerated (2-8°C): up to 7 days; Frozen (-20°C or below): up to 30 days. For forensic specimens, freeze at -20°C if testing is delayed beyond 48 hours.
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–72 hours
Order
routine

What is this test?

The Barbiturates Urine Test is a laboratory test that detects the presence of barbiturate drugs in your urine. Barbiturates are a class of prescription medications that act as central nervous system depressants. They are typically used to treat anxiety, insomnia, and seizure disorders.

Why might I need this test?

Your healthcare provider may order this test for several reasons: (1) Routine drug screening for employment or legal purposes, (2) Monitoring patients who are prescribed barbiturate medications to ensure proper use, (3) Investigating symptoms of possible barbiturate overdose or poisoning, (4) Evaluating unexplained symptoms such as excessive drowsiness, confusion, or breathing problems.

How is the test performed?

A urine sample is collected in a sterile container. The sample is then analyzed in a laboratory using immunoassay techniques or gas chromatography-mass spectrometry (GC-MS) for confirmation. You may be asked to provide the sample under supervision to ensure sample integrity, especially for legal or employment testing.

What do the results mean?

Results are typically reported as either 'Positive' (barbiturates detected) or 'Negative' (no barbiturates detected). A positive result indicates recent barbiturate use. The test does not measure the amount of drug taken or indicate impairment. Your healthcare provider will interpret the results in context with your medical history and symptoms.

Reference range

Negative (cutoff threshold typically 200-300 ng/mL for screening; varies by laboratory). Positive indicates the presence of barbiturate-class compounds at or above the assay cutoff.N/A

Specimen: urine

No fasting required. Patients should be advised that certain prescription medications (e.g., phenobarbital, butalbital, secobarbital) and over-the-counter preparations may produce positive results. Collection should be observed for forensic or workplace drug testing purposes to prevent adulteration or substitution.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

How long do barbiturates stay in urine?
Barbiturates can be detected in urine for several days to weeks after use, depending on the specific drug, dosage, frequency of use, and individual metabolism. Short-acting barbiturates may be detectable for 2-4 days, while long-acting ones like phenobarbital may be detectable for 2-3 weeks.
Do I need to prepare for the test?
No special preparation is typically required. However, you should inform your healthcare provider about all medications, supplements, and herbal products you are taking, as certain substances may affect test results. For supervised collections, bring valid identification.
Can a positive result mean I took someone else's medication?
A positive result indicates barbiturates are present in your urine, regardless of how they entered your system. Certain prescription medications, foods, or supplements are not known to cause false positive results for barbiturates. Discuss any legitimate prescriptions with your healthcare provider.
Will the test show how much I took?
No. This qualitative test only indicates whether barbiturates are present or absent. It does not determine the amount consumed or the level of impairment. Additional testing may be needed for quantitative analysis.
  1. 1
    MedlinePlus - Drug TestingSource
  2. 2
    Mayo Clinic Laboratories - Barbiturates, UrineSource

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