Complete Blood Count (CBC) Test: What It Measures and Why Your Doctor Ordered It
This test confirms the presence of benzodiazepines in urine using a sensitive mass/volume method to verify results from initial screening.
{"This is a confirmatory test that measures benzodiazepine levels in urine","It uses mass spectrometry to accurately identify and quantify specific benzodiazepine drugs","The test helps verify positive screening results or monitor medication compliance","A cutoff value determines whether the result is considered positive or negative","Results are typically reported as detected/not detected relative to the cutoff"}
Key facts at a glance
- LOINC
- 19284-9
- Short code
- BENZCFM
- Synonyms
- Benzodiaz CtO Ur Cfm-mCnc
- Category
- chemistry
- Sample
- urine
- Container
- Sterile, leak-proof urine collection container (preferably a screw-capped, preservative-free container)
- Units
- N/A
- Ref high
- 200
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- confirm
- CPT
- 80347 (when performed with definitive identification, e.g., GC-MS or LC-MS/MS) or 80346 (for benzodiazepines, quantitative)
- SNOMED
- 272910001
- Specimen volume
- 30-50 mL of random urine sample
- Stability
- Room temperature: 48 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. For extended storage, freeze at -20°C or lower.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 24–72 hours
- Order
- routine
The complete blood count (CBC) is a common blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets, giving your doctor a broad picture of your overall health.
The Benzodiazepine Confirmatory Test is a specialized urine test that uses mass spectrometry technology to accurately detect and identify benzodiazepine drugs in your urine. Unlike basic screening tests, this confirmatory method can distinguish between different types of benzodiazepines and measures them against a specific cutoff value to determine if the level is significant.
A small sample of blood is drawn from a vein in your arm, usually at the inside of your elbow, and the sample is sent to a laboratory where automated equipment counts and measures each type of blood cell in your sample.
You will be asked to provide a urine sample in a clean container. The laboratory will then analyze your sample using sophisticated equipment that can measure the mass and concentration of benzodiazepine substances. The results are compared against a predetermined cutoff value. If the measured level is above the cutoff, the result is reported as 'detected' or positive. If below the cutoff, it is reported as 'not detected' or negative.
Your doctor may order a CBC as part of a routine checkup or to help diagnose conditions such as anemia, infection, inflammation, or bleeding problems, and to monitor an existing condition or the effects of treatment over time.
This confirmatory test is typically ordered after a preliminary screening test shows a positive result. It provides more accurate and specific information about benzodiazepine use. Healthcare providers may also order this test to monitor patients taking benzodiazepine medications for pain, anxiety, or sleep disorders to ensure proper medication compliance.
A CBC usually requires no special preparation, so you can normally eat and drink beforehand, but tell your doctor about all medications and supplements you take, since some of these can affect your test results.
For this test, you should inform your healthcare provider about all prescription medications, over-the-counter drugs, and supplements you are taking, as some substances may affect the test results. Avoid changing your normal medication routine unless specifically instructed by your doctor. Drink normal amounts of fluid unless otherwise directed.
Reference range
Negative (below cutoff threshold). The standard confirmatory cutoff for benzodiazepines in urine is 200 ng/mL (or 100 ng/mL depending on laboratory protocol and specific analyte).N/A
No special preparation required. Patients should be informed that certain prescription medications and over-the-counter supplements may cross-react with benzodiazepine immunoassays. A confirmatory test is typically ordered following a positive screening result.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This confirmatory test is clinically important because it provides definitive evidence of benzodiazepine use with high accuracy. It helps healthcare providers distinguish between true positive results and false positives that may occur with screening tests. The test is valuable in substance abuse treatment programs, pain management, medication compliance monitoring, and forensic settings. Results above the cutoff indicate significant benzodiazepine exposure, while results below suggest no significant presence or that the drug has been eliminated from the body.
Frequently asked questions
Will this test show how much benzodiazepine I took?
How long do benzodiazepines stay detectable in urine?
Can my prescription medications affect the test results?
Is this test confidential?
What happens if my test is positive?
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