Barbituratesurqlscn300ngml
This test detects barbiturates in your urine to check for recent use of certain medications or substances.
{"Detects barbiturate drugs in urine sample","Used to monitor medication compliance or detect substance use","Results show positive/negative rather than exact levels","Positive results may require confirmation testing","Cutoff threshold is 300 ng/mL"}
Key facts at a glance
- LOINC
- 70139-1
- Short code
- BARB-U
- Synonyms
- Barbiturates Ur Ql Scn>300 ng/mL
- Category
- chemistry
- Sample
- urine
- Container
- Sterile, tamper-evident, leak-proof urine collection cup without preservatives; preferably a screw-cap, wide-mouth, single-use container. Chain-of-custody container required for medico-legal, forensic, or workplace drug testing scenarios.
- Units
- N/A
- Ref low
- 1
- Ref high
- 3
- Critical range
- — – 300 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- screen-ng-ml
- CPT
- 80307
- SNOMED
- 1023761000119107
- Specimen volume
- 30-50 mL of urine (minimum 10 mL for screening); insufficient volumes should be rejected.
- Stability
- Ambient temperature: up to 48 hours. Refrigerated (2-8°C): up to 7 days. Frozen (-20°C or below): up to 30 days or longer for forensic retention. Avoid repeated freeze-thaw cycles. For medico-legal samples, follow chain-of-custody and storage regulations per laboratory policy and applicable law.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 2–24 hours
- Order
- routine
What is this test?
The Barbiturates Urine Screening Test is a diagnostic test that detects the presence of barbiturates in your urine. Barbiturates are a class of medications that act as central nervous system depressants, commonly prescribed for conditions such as anxiety, insomnia, seizure disorders, and as anesthetic agents during surgery. This screening test uses a method that can identify whether barbiturate substances are present above a specific threshold of 300 ng/mL.
The test is performed on a urine sample that you provide, typically collected in a sterile container. The screening method is designed to be initial testing—if the result is positive, confirmatory testing is usually recommended to identify the specific type of barbiturate present.
Reference range
Cutoff: 300 ng/mL. Negative: Below 300 ng/mL (barbiturates not detected at or above the screening threshold). Positive: Greater than 300 ng/mL (barbiturates detected at or above the screening threshold). Note: This is a qualitative/semi-quantitative screen; quantitative confirmation is recommended for clinical or forensic decision-making. Detection window in urine varies based on the specific barbiturate: short-acting (e.g., pentobarbital, secobarbital) 1-3 days; intermediate-acting (e.g., amobarbital, butabarbital) 3-7 days; long-acting (e.g., phenobarbital) up to 14-21 days or longer with chronic use.N/A
No fasting required. Patient should be informed that barbiturates can be detected in urine for variable periods depending on the specific agent, dose, duration of use, and individual metabolism. A supervised or witnessed collection may be required for forensic, workplace, or medico-legal testing. Patients should disclose all prescription and over-the-counter medications, as some barbiturates (e.g., phenobarbital, butalbital) are prescribed therapeutically.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used for therapeutic drug monitoring to ensure patients are taking their prescribed barbiturate medications as directed by their healthcare provider. It is also used in substance abuse screening programs, pre-employment testing, and in emergency clinical settings when toxicological evaluation is needed. Barbiturate use detection is important because these medications have a high potential for dependence and abuse, and overdose can lead to serious complications including respiratory depression, coma, or death. The test helps healthcare providers assess medication compliance, evaluate unexplained symptoms, or determine if barbiturates may be contributing to a patient's medical condition.
Frequently asked questions
How long do barbiturates stay detectable in urine?
Will a positive result mean I am taking barbiturates illegally?
Do I need to prepare specially for this test?
What happens if my result is positive?
Can false positive results occur?
Sources
- 1
- 2
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.
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