Benzodiazserplqlscn
A screening test to detect the presence of benzodiazepine drugs in your blood.
{"This test checks if benzodiazepine medications are present in your blood","It helps doctors monitor drug levels or investigate suspected overdose","Common benzodiazepines include diazepam, lorazepam, and alprazolam","The test uses a blood sample drawn from a vein","Results are typically reported as positive or negative"}
Key facts at a glance
- LOINC
- 46976-7
- Short code
- BENZO-S
- Synonyms
- Benzodiaz SerPl Ql Scn
- Category
- chemistry
- Sample
- serum
- Container
- Red-top (no additive) or serum separator tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- screen
- CPT
- 80307
- SNOMED
- 396877001
- Specimen volume
- 1-2 mL of serum or plasma
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
The benzodiazepine test is a screening test that detects whether benzodiazepine medications are present in your blood. Benzodiazepines are a class of prescription drugs commonly used to treat anxiety, insomnia, seizures, and muscle spasms. Examples include diazepam (Valium), lorazepam (Ativan), alprazolam (Xanax), and clonazepam (Klonopin).
This test uses a blood sample to screen for the presence of these drugs. It is not typically used to measure exact drug levels, but rather to determine whether any benzodiazepine is present in your system.
Why might I need this test?
Your doctor may order this test for several reasons: to monitor if you are taking your prescribed medication, to investigate symptoms of suspected overdose or poisoning, to check for drug use before surgery, or to evaluate unexplained symptoms such as excessive drowsiness, confusion, or breathing problems.
How is the test performed?
A healthcare professional will draw a small amount of blood from a vein in your arm using a needle. The blood sample is then sent to a laboratory for analysis. The test itself involves adding the blood sample to a test system that detects the presence of benzodiazepine compounds.
What do the results mean?
Results are typically reported as either positive or negative. A positive result means benzodiazepines were detected in your blood. A negative result means no benzodiazepines were detected. It is important to discuss your results with your doctor, who will interpret them based on your medical history and the reason for testing.
Reference range
Negative (Cutoff: 200 ng/mL for nordiazepam or equivalent benzodiazepine metabolite)N/A
No fasting required. Inform the laboratory of all prescription medications, over-the-counter drugs, and supplements being taken, as benzodiazepines are commonly prescribed and results may be expected.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings2
Frequently asked questions
Do I need to fast before this test?
How long do benzodiazepines stay in blood?
Will my prescription affect the test results?
Is this test accurate?
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