Blood Test: What You Need to Know About This Common Laboratory Test
A urine test to detect the presence of benzodiazepine medications in your system.
{"This test checks if benzodiazepine drugs are in your urine","It is commonly used for medication monitoring or substance abuse screening","The test uses a cutoff value to determine positive or negative results","Results are typically available within a few days","Certain foods and medications may affect test results"}
Key facts at a glance
- LOINC
- 19064-5
- Short code
- BENZ-U
- Synonyms
- Benzodiaz CtO Ur-mCnc
- Category
- chemistry
- Sample
- urine
- Container
- Sterile, leak-proof urine collection container without preservatives. For chain-of-custody specimens, use tamper-evident container per SAMHSA guidelines.
- Units
- N/A
- Ref low
- 0
- Ref high
- 200
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunoassay screening (e.g., EIA, CEDIA, EMIT, KIMS, or FPIA) with confirmation by Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
- CPT
- 80307 (presumptive drug class screening), G0480-G0483 (definitive drug confirmation depending on payer)
- SNOMED
- 28130008
- Specimen volume
- Minimum 10 mL; optimal 30-50 mL of random urine
- Stability
- Room temperature: 2 days; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days for negative samples, indefinite for positive samples. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–72 hours
- Order
- routine
A blood test is a routine laboratory procedure in which a small sample of your blood is analyzed to evaluate your overall health, screen for medical conditions, monitor an existing diagnosis, or check how well organs such as the liver, kidneys, and thyroid are working.
The Benzodiazepines urine test is a screening test that detects whether benzodiazepine medications are present in your urine. Benzodiazepines are a class of prescription medications commonly used to treat anxiety, insomnia, seizures, and muscle spasms. Common examples include diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan), and clonazepam (Klonopin).
The test is performed by a trained healthcare professional who wraps a band around your upper arm, cleans the skin, and inserts a thin needle into a vein, usually in your arm, to collect one or more small tubes of blood. The procedure takes only a few minutes, and the sample is then sent to a laboratory for analysis.
A urine sample is collected in a sterile container. The sample is then analyzed in a laboratory using immunoassay techniques. The test uses a specific cutoff concentration to determine whether the result is positive or negative. If the concentration of benzodiazepines is above the cutoff, the result is positive; if below, the result is negative.
Follow any instructions from your healthcare provider. Some blood tests require fasting for 8 to 12 hours, during which you may drink water but should avoid food, coffee, and juice unless told otherwise. Take your regular medications unless advised to skip them, drink plenty of water, and wear a sleeve that can be rolled up easily.
No special preparation is typically required. However, you should inform your healthcare provider about all medications, supplements, and herbal products you are taking, as some substances may interfere with the test results. It is important to provide a complete medication history, including any prescription benzodiazepines you are legitimately taking.
Your results are compared with established reference ranges. Values that fall outside the normal range may point to an infection, anemia, a metabolic problem, or another condition, but a single abnormal result rarely provides a diagnosis on its own. Your healthcare provider will review the findings with you, explain what they mean in the context of your symptoms and medical history, and recommend any follow-up testing or treatment.
A negative result means no benzodiazepines were detected above the cutoff level. A positive result indicates that benzodiazepines or their metabolites were detected above the cutoff level. Your healthcare provider will interpret the results in the context of your medical history and current medications. If you are taking prescribed benzodiazepines, a positive result is expected.
Reference range
Negative: Below the established cutoff concentration (typically 200 ng/mL or 300 ng/mL depending on laboratory protocol). Positive results indicate benzodiazepine class exposure at or above the screening threshold and require confirmatory testing for specific identification.N/A
No fasting required. Patients should be advised that certain prescription and over-the-counter medications may cause positive results. Patient consent may be required based on institutional policy. Collect specimen prior to administration of next scheduled dose when monitoring compliance.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used for medication monitoring to ensure patients are taking their prescribed benzodiazepines as directed. It is also used in substance abuse screening programs, forensic investigations, and workplace drug testing. The test can help healthcare providers assess medication adherence, detect unauthorized drug use, or monitor patients in substance abuse treatment programs.
Benzodiazepines can remain detectable in urine for several days after use, depending on the specific medication, dosage, frequency of use, and individual metabolism. Longer-acting benzodiazepines like diazepam may be detectable for up to a week or more, while shorter-acting ones may be detectable for 1-3 days.
Frequently asked questions
Will eating certain foods affect the test results?
How long do benzodiazepines stay in urine?
Can the test tell me how much medication I took?
What should I do if my test is positive?
Sources
- 1
- 2
- 3
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