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Complete Blood Count (CBC): What This Common Blood Test Measures and What Your Results Mean

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

A urine test that checks for the presence of benzodiazepines, a class of medications commonly used to treat anxiety, insomnia, and seizures.

Quick summary

{"This test detects benzodiazepine medications in your urine","It is used to monitor medication compliance or detect potential drug misuse","Results are reported as positive or negative (presence or absence)","Certain medications may cause false positive results","Detection time varies from days to weeks depending on the specific drug"}

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

Key facts at a glance

LOINC
14316-4
Short code
BENZ-U
Synonyms
Benzodiaz Ur Ql Scn
Category
chemistry
Sample
urine
Container
Sterile, leak-proof urine container without preservative (plastic screw-cap cup); preferred chain-of-custody container if legally required
Units
N/A
Ref low
100
Ref high
300
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
screen
CPT
80307
SNOMED
48467002
Specimen volume
30-60 mL (minimum 10 mL)
Stability
Room temperature: up to 24 hours; Refrigerated (2-8°C): up to 7 days; Frozen (-20°C): up to 30 days for confirmation testing
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is a Complete Blood Count (CBC) and what does this test measure in your blood?

The Benzodiazepine Urine Screening Test is a laboratory test that detects the presence of benzodiazepines in your urine. Benzodiazepines are a class of prescription medications commonly used to treat conditions such as anxiety, insomnia, muscle spasms, and seizures. Common benzodiazepines include diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan), clonazepam (Klonopin), and temazepam (Restoril).

Why might your doctor order a Complete Blood Count (CBC) as part of your routine care?

This test may be ordered for several reasons: to monitor patient compliance with prescribed benzodiazepine therapy, to detect unauthorized or illicit use of benzodiazepines, as part of a routine drug screening (such as for employment or legal purposes), or to help healthcare providers assess medication effectiveness. It may also be used in emergency settings to identify the cause of unexplained symptoms such as excessive drowsiness or confusion.

How is a Complete Blood Count (CBC) performed, and what should you expect during the blood draw?

A urine sample is collected in a clean container. The sample is then analyzed in a laboratory using immunoassay screening methods. This initial screening test is qualitative, meaning it provides a positive or negative result rather than measuring the exact amount of drug in your system. If the screening test is positive, confirmatory testing may be performed using more specific methods such as gas chromatography-mass spectrometry (GC-MS) to identify the exact benzodiazepine present.

What do the results of a Complete Blood Count (CBC) mean, and what can high or low values indicate?

A negative result means no benzodiazepines were detected in your urine at the time of testing. A positive result indicates that benzodiazepines or their metabolites were detected. It is important to note that different benzodiazepines remain detectable in urine for different lengths of time—generally ranging from several days to over a week after the last dose. Your healthcare provider will interpret your results in the context of your medical history and prescribed medications.

Are there any limitations or important considerations to keep in mind when interpreting your CBC results?

This screening test has some limitations. Certain medications, such as some antidepressants (sertraline, venlafaxine), antipsychotics (quetiapine), or the anti-nausea medication metoclopramide, may cause false positive results. Additionally, some benzodiazepine-like substances may not be detected by all screening methods. The test does not indicate impairment levels or dosage amounts. Always inform your healthcare provider about all medications and supplements you are taking before undergoing this test.

Reference range

Negative (cutoff typically 100-300 ng/mL depending on assay; commonly 200 ng/mL for most benzodiazepines)N/A

Specimen: urine

No fasting required. Patient should be informed that certain prescription medications (e.g., alprazolam, lorazepam, diazepam, clonazepam, temazepam) may cause positive results. Inform clinician of all medications and supplements prior to collection.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

The benzodiazepine urine screening test is clinically significant for medication monitoring and drug abuse detection. It helps healthcare providers ensure patients are taking their prescribed medications appropriately, identify potential misuse or diversion of controlled substances, and evaluate unexplained symptoms that may be related to benzodiazepine use or overdose. The test is also valuable in substance abuse treatment programs and pain management settings where opioid medications are prescribed alongside benzodiazepines, as this combination carries significant safety concerns.

Frequently asked questions

How long do benzodiazepines stay in urine?
Detection time varies depending on the specific benzodiazepine, dosage, frequency of use, and individual factors such as metabolism and kidney function. Short-acting benzodiazepines (like alprazolam) may be detectable for 1-3 days, while longer-acting ones (like diazepam) can be detected for 1-2 weeks or longer after the last dose.
Will a positive result show which specific benzodiazepine I took?
Standard screening tests only indicate whether benzodiazepines are present, not the specific type. If identification of the exact substance is needed, a confirmatory test (such as GC-MS) can be performed. Discuss this with your healthcare provider if specific identification is important for your care.
Can over-the-counter medications cause a positive result?
Some over-the-counter medications and herbal supplements are unlikely to cause a positive result. However, certain prescription medications like some antidepressants (sertraline, fluoxetine) and antipsychotics may occasionally cause false positive results. Always inform your healthcare provider about all medications you are taking.
Do I need to prepare for this test?
No special preparation is typically required. You should continue taking your prescribed medications as directed unless your healthcare provider instructs otherwise. Bring a list of all medications, supplements, and vitamins you are currently taking to your appointment.
Can this test detect if someone is addicted to benzodiazepines?
This test can detect the presence of benzodiazepines but cannot diagnose addiction on its own. A positive result combined with other clinical assessments helps healthcare providers evaluate patterns of use. Dependence and addiction are diagnosed through comprehensive evaluation including history, symptoms, and behavior patterns.
  1. 1
    MedlinePlus - Benzodiazepine ScreenSource
  2. 2
    Mayo Clinic Laboratories - Benzodiazepines, UrineSource
  3. 3
    LabCorp - Benzodiazepines, 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