Test Catalog

Test Id : BNZU

Benzodiazepines Confirmation, Random, Urine

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detecting drug use involving benzodiazepines such as alprazolam, chlordiazepoxide, clonazepam, diazepam, midazolam, oxazepam, temazepam, clobazam, flunitrazepam, flurazepam, lorazepam, prazepam, triazolam, and zolpidem

Method Name
A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Benzodiazepines Confirmation, U

Lists additional common names for a test, as an aid in searching

7-Amino Flunitrazepam (Metabolite of Flunitrazepam) (Rohypnol)


Alprazolam (Xanax)

Ativan (Lorazepam)


Chlordiazepoxide (Librium)


Dalmane (Flurazepam)

Diazepam (Valium)

Flunitrazepam (Rohypnol)

Flurazepam (Dalmane)

Halcion (Triazolam)

Hydroxy-Ethyl Flurazepam (Metabolite of Flurazepam)

Librium (Chlordiazepoxide)

Lorazepam (Ativan)

Oxazepam (Serax)

Restoril (Temazepam)

Rohypnol (Flunitrazepam)

Serax (Oxazepam)

Temazepam (Restoril)

Triazolam (Halcion)

Valium (Diazepam)

Xanax (Alprazolam)

Specimen Type
Describes the specimen type validated for testing


Ordering Guidance

For situations where chain of custody is required, a Chain of Custody Kit (T282) is available. For chain-of-custody testing, order BNZX / Benzodiazepines Confirmation, Chain of Custody, Random, Urine.


Additional drug panels and specific requests are available. Call 800-533-1710 or 507-266-5700.

Additional Testing Requirements

If urine creatinine is required or adulteration of the sample is suspected, order ADULT / Adulterants Survey, Random, Urine.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Supplies: Aliquot Tube, 5 mL (T465)

Collection Container/Tube: Plastic urine container

Submission Container/Tube: Plastic, 5-mL tube

Specimen Volume: 1 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative

Additional Information:

1. No specimen substitutions.

2. STAT requests are not accepted for this test.

3. Submitting less than 1 mL will compromise our ability to perform all necessary testing.


Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross icterus Reject

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 7 days
Frozen 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detecting drug use involving benzodiazepines such as alprazolam, chlordiazepoxide, clonazepam, diazepam, midazolam, oxazepam, temazepam, clobazam, flunitrazepam, flurazepam, lorazepam, prazepam, triazolam, and zolpidem

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Benzodiazepines are any of a group of compounds having a common molecular structure and acting similarly as depressants of the central nervous system. As a class of drugs, benzodiazepines are among the drugs most commonly prescribed in the western hemisphere because of their efficacy, safety, low addiction potential, minimal side effects, and high public demand for sedative and anxiolytic agents.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.



Cutoff concentrations by liquid chromatography- tandem mass spectroscopy:

Alprazolam: 10 ng/mL

Alpha-hydroxyalprazolam: 10 ng/mL

Chlordiazepoxide: 10 ng/mL

Clonazepam: 10 ng/mL

7-Aminoclonazepam: 10 ng/mL

Diazepam: 10 ng/mL

Nordiazepam: 10 ng/mL

Midazolam: 10 ng/mL

Alpha-hydroxy midazolam: 10 ng/mL

Oxazepam: 10 ng/mL

Temazepam: 10 ng/mL

Clobazam: 10 ng/mL

N-Desmethylclobazam by LC-MS/MS: 10 ng/mL

Flunitrazepam: 10 ng/mL

7-Aminoflunitrazepam: 10 ng/mL

Flurazepam: 10 ng/mL

2-Hydroxy ethyl flurazepam: 10 ng/mL

Lorazepam: 10 ng/mL

Prazepam: 10 ng/mL

Triazolam: 10 ng/mL

Alpha-hydroxy triazolam: 10 ng/mL

Zolpidem: 10 ng/mL

Zolpidem phenyl-4-carboxylic acid: 10 ng/mL

Provides information to assist in interpretation of the test results

Benzodiazepines are extensively metabolized, and the parent compounds are not detected in urine. This test screens for (and confirms) the presence of:


-Alpha-hydroxyalprazolam (metabolite of alprazolam)



-7-Aminoclonazepam (metabolite of clonazepam)

-Diazepam (separate prescribable drug and metabolite of medzazepam)

-Nordiazepam (metabolite of clorazepate, halazepam, prazepam, diazepam and medazepam)


-Alpha-hydroxy midazolam (metabolite of midazolam)

-Oxazepam (separate prescribable drug and metabolite of clorazepate, halazepam, prazepam, medazepam, temazepam, and diazepam)

-Temazepam (separate prescribable drug and metabolite of medazepam and diazepam)


-N-Desmethylclobazam (metabolite of clobazam)


-7-Aminoflunitrazepam (metabolite of flunitrazepam)


-2-Hydroxy ethyl flurazepam (metabolite of flurazepam)




-Alpha-hydroxy triazolam (metabolite of triazolam)


-Zolpidem phenyl-4-carboxylic acid (metabolite of zolpidem)


The clearance half-life of long-acting benzodiazepines is more than 24 hours. It takes 5 to 7 half-lives to clear 98% of a drug dose. Therefore, the presence of a long-acting benzodiazepine greater than the limit of quantification indicates exposure within a 5 to 20-day interval preceding specimen collection. Following a dose of diazepam, the drug and its metabolites appear in the urine within 30 minutes. Peak urine output is reached between 1 and 8 hours. See Mayo Clinic Laboratories Drugs of Abuse Testing Guide for additional information including metabolism, clearance (half-life), and approximate detection times.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Gudin JA, Mogali S, Jones JD, Comer SD: Risks, management, and monitoring of combination of opioid, benzodiazepines, and/or alcohol use. Postgrad Med. 2013 Jul;125(4):115-130. doi: 10.3810/pgm.2013.07.2684

2. Manchikanti L, Abdi S, Atluri S, et al: American Society of Interventional Pain Physicians (ASIPP) guidelines for responsible opioid prescribing in chronic non-cancer pain: Part 2--guidance. Pain Physician. 2012 Jul;15(3 Supp):S67-116

3. Barkin RL: In: Baselt RC, ed. Disposition of Toxic Drugs and Chemicals in Man. 8th ed. Biomedical Publications; 2008

4. Langman LJ, Bechtel LK, Meier BM, Holstege C: Clinical toxicology. In: Rifai N, Horvath AR, Wittwer CT, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:1328-1333

Method Description
Describes how the test is performed and provides a method-specific reference

Benzodiazepines are extensively metabolized by the liver and subsequently exist in the urine primarily as conjugated esters (-glucuronides). The conjugated metabolites are cleaved during a mild hydrolysis utilizing the enzyme glucuronidase. Stable isotope forms of the compounds are added as internal standards to account for extraction losses. An aliquot of the hydrolyzed sample is diluted and the analytes are separated by liquid chromatography tandem mass spectroscopy (LC-MS/MS) and analyzed by multiple reaction monitoring.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Tuesday through Friday, Sunday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

3 to 6 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.




G0480 (if appropriate)

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
BNZU Benzodiazepines Confirmation, U 90890-5
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
608256 Alprazolam by LC-MS/MS 59615-5
608257 Alpha-Hydroxyalprazolam by LC-MS/MS 16348-5
608258 Chlordiazepoxide by LC-MS/MS 20522-9
608259 Clonazepam by LC-MS/MS 16229-7
608260 7-aminoclonazepam by LC-MS/MS 51776-3
608261 Diazepam by LC-MS/MS 16227-1
608262 Nordiazepam by LC-MS/MS 16228-9
608263 Midazolam by LC-MS/MS 16233-9
608264 Alpha-Hydroxy Midazolam by LC-MS/MS 59590-0
608265 Oxazepam by LC-MS/MS 16201-6
608266 Temazepam by LC-MS/MS 20559-1
608267 Clobazam by LC-MS/MS 59635-3
608268 N-Desmethylclobazam by LC-MS/MS 97160-6
608269 Flunitrazepam by LC-MS/MS 20528-6
608270 7-aminoflunitrazepam by LC-MS/MS 51777-1
608271 Flurazepam by LC-MS/MS 16231-3
608272 2-Hydroxy Ethyl Flurazepam by LC-MS/MS 97159-8
608273 Lorazepam by LC-MS/MS 17088-6
608274 Prazepam by LC-MS/MS 17479-7
608275 Triazolam by LC-MS/MS 16232-1
608276 Alpha-Hydroxy Triazolam by LC-MS/MS 49876-6
608277 Zolpidem by LC-MS/MS 72770-1
608278 Zolpidem Phenyl-4-Carboxylic acid by LC-MS/MS 72768-5
608448 Benzodiazepines Interpretation 16195-0

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
Test Changes - Specimen Information 2021-10-25