Understanding Your Laboratory Test: Purpose, Procedure, and How to Interpret Your Results
A urine test to detect the presence of barbital, a barbiturate medication, in your system.
{"This test checks if barbital (a sedative medication) is present in your urine","It is commonly used to monitor medication compliance or detect unauthorized drug use","The test results are reported as either 'Positive' (present) or 'Negative' (not detected)"}
Key facts at a glance
- LOINC
- 12360-4
- Short code
- URBARB
- Synonyms
- Barbital Ur Ql
- Category
- chemistry
- Sample
- urine
- Container
- Sterile, tamper-evident urine specimen container; forensic collection container with chain-of-custody documentation if required
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Gas Chromatography-Mass Spectrometry (GC-MS) or Immunoassay screening
- CPT
- 80307
- SNOMED
- 250679005
- Specimen volume
- 30-50 mL random urine specimen; minimum 10 mL required for analysis
- Stability
- Refrigerated (2-8°C): 7 days; Frozen (-20°C): 30 days; Room temperature: 48 hours. For forensic specimens, follow chain-of-custody storage requirements.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 24–72 hours
- Order
- routine
This is a laboratory test that analyzes a sample of your blood, urine, or other body tissue to give your healthcare provider important information about how your body is functioning and whether there are any signs of illness or abnormality.
The Barbital Urine Test is a qualitative laboratory test that detects whether barbital, a barbiturate-class medication, is present in your urine. Barbiturates are sedative-hypnotic drugs that were historically used to treat anxiety, insomnia, and seizures. This test does not measure the amount of barbital in your system—only whether it is detected or not.
Your doctor may order this test to help diagnose a medical condition, investigate symptoms you have been experiencing, screen for disease before symptoms appear, or monitor how well an existing condition or ongoing treatment is being managed over time.
Healthcare providers may order this test for several reasons: (1) To monitor patient compliance with prescribed barbital therapy, (2) To detect unauthorized or recreational use of barbiturates, (3) As part of a broader drug screening panel, or (4) To investigate symptoms that may be related to barbiturate use or overdose.
A trained healthcare professional will collect a small sample, usually by drawing blood from a vein in your arm with a fine needle or by asking you to provide a urine specimen, and the sample is then sent to a laboratory where it is carefully analyzed.
A urine sample is collected in a clean container. The sample is then analyzed in a laboratory using immunoassay or chromatography methods to detect the presence of barbital or its metabolites. No special preparation is typically required, though you should inform your healthcare provider about any medications or supplements you are taking.
Your results are compared with a reference range, which represents the values considered typical for healthy people; results can be influenced by your age, sex, medications, and overall health, so your healthcare provider will review them with you and explain what they mean for your care.
Results are typically reported as 'Positive' (barbital detected) or 'Negative' (barbital not detected). A positive result may indicate legitimate prescribed use, unauthorized use, or exposure to barbiturate-containing products. A negative result suggests no detectable barbital is present, though this does not rule out use if the drug has been fully metabolized and eliminated from your system.
Reference range
Negative: Barbital not detected in urine. Cutoff threshold: 200 ng/mL (screening); 100 ng/mL (confirmation by GC-MS).N/A
No special preparation required. Patients should be informed that the test detects barbiturate use and that certain prescription medications containing barbiturates may produce positive results. Collect urine prior to administration of diuretics when possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Barbital is a long-acting barbiturate that was previously used as a sedative and anticonvulsant. Detection of barbital in urine helps healthcare providers assess medication adherence in patients with legitimate prescriptions, identify potential drug abuse or diversion, and evaluate unexplained symptoms such as excessive drowsiness, confusion, or respiratory depression. This test is particularly relevant in addiction medicine, psychiatric care, and pain management settings.
Frequently asked questions
How long does barbital stay detectable in urine?
Will a positive result automatically mean I have a problem?
Can other medications cause a false positive result?
Do I need to fast or prepare for this test?
Sources
- 1
- 2
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
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