Valium is the brand name for diazepam, a long acting benzodiazepine prescribed for anxiety, muscle spasm, seizure disorders, and alcohol withdrawal. Whether it shows up on a drug test depends entirely on which panel the employer or clinic chooses. Diazepam and its metabolites are a common target of the benzodiazepine (BZO) immunoassay used on many workplace urine cups, but benzodiazepines as a class are not part of the federally mandated five panel test that governs safety sensitive transportation testing. Understanding that distinction, along with how screening and lab confirmation actually work, matters more than a simple yes or no answer.
What diazepam is and how the body processes it
Diazepam is a long acting benzodiazepine that the liver breaks down through the CYP2C19 and CYP3A4 enzyme pathways into several active metabolites. According to the National Institutes of Health StatPearls reference, the main metabolite is desmethyldiazepam, also called nordiazepam, with oxazepam and temazepam produced as additional active metabolites. The average half life of diazepam itself runs around 46 to 48 hours, but nordiazepam has a much longer terminal half life, cited at up to 100 hours. Diazepam and its metabolites are excreted mainly in the urine and can accumulate with repeated dosing, which is why detection windows for chronic or higher dose use tend to run longer than for a single low dose.
That long half life is also why diazepam is sometimes used clinically to taper other benzodiazepines or to manage acute alcohol withdrawal, since its slow elimination smooths out the drop in blood levels compared to a shorter acting drug. For drug testing purposes, the practical takeaway is that a positive benzodiazepine screen after diazepam use does not by itself tell an employer or lab how recently the drug was taken, since detection windows vary widely by dose, frequency, individual metabolism, and which metabolite the assay is actually measuring.
How the BZO immunoassay screens for diazepam
Most workplace urine drug test cups that include benzodiazepine screening use an immunoassay calibrated to a target benzodiazepine compound, commonly oxazepam, with cross reactivity extended to related compounds in the same class. Because diazepam converts into oxazepam and temazepam as part of normal metabolism, a diazepam user's urine typically contains a mix of the parent drug and several metabolites that most BZO immunoassays are built to catch. Manufacturers generally calibrate these screens with an initial cutoff in the range of 200 to 300 nanograms per milliliter, though the exact cutoff and cross reactivity profile depends on the specific assay and manufacturer, so employers should confirm the cutoff their chosen cup or cassette actually uses rather than assuming a single industry standard number.
Cross reactivity is also why a benzodiazepine screen is described as presumptive rather than definitive. The immunoassay reacts to a family of structurally similar molecules, not to diazepam specifically, so a non negative result only means something in that chemical family was present above the cutoff. Identifying diazepam and its individual metabolites requires confirmation testing.
| Factor | What it means for testing |
|---|---|
| Drug class | Benzodiazepine, DEA Schedule IV controlled substance |
| Active metabolites | Nordiazepam (desmethyldiazepam), oxazepam, temazepam |
| Elimination half life | Diazepam approximately 46 to 48 hours; nordiazepam up to 100 hours |
| Initial screen | Benzodiazepine (BZO) immunoassay, typical cutoff in the 200 to 300 ng/mL range depending on manufacturer |
| Confirmation method | GC-MS or LC-MS/MS, identifies diazepam and its specific metabolites |
| Federal five panel (DOT) | Benzodiazepines are not part of the federally mandated five panel test; many non-DOT employer panels add a BZO screen separately |
| Prescription documentation | Reviewed by the Medical Review Officer before a result is reported to an employer |
Screening versus confirmation: why the distinction matters here
An immunoassay screen is a presumptive test that reacts to a class of chemically similar molecules. Because diazepam metabolizes into oxazepam and temazepam, which are themselves prescribed as standalone medications, a screen positive for benzodiazepines cannot on its own tell a lab or employer which specific drug was used. A non negative screen should go to confirmation testing by gas chromatography mass spectrometry (GC-MS) or liquid chromatography tandem mass spectrometry (LC-MS/MS), which separates and identifies individual compounds rather than reacting to a class. Confirmation can distinguish diazepam and nordiazepam from other benzodiazepines that produce overlapping metabolites, which is important for an accurate record and for the Medical Review Officer's review.
Does DOT drug testing include Valium?
No. Benzodiazepines, including diazepam, are not part of the drug panel that federal regulations require laboratories to test for under the Department of Transportation program. The current federal cutoff table in 49 CFR 40.85 lists only marijuana metabolites, cocaine metabolites, opioids (including codeine, morphine, hydrocodone, hydromorphone, oxycodone, oxymorphone, and 6-acetylmorphine), phencyclidine, and amphetamines and methamphetamine, along with MDMA and MDA. Diazepam and other benzodiazepines are not on that list. Employers who want benzodiazepine coverage for DOT covered employees, or for any workforce, have to add a separate non-DOT panel or a specific BZO component through their testing program, and that decision should be documented clearly in a written drug testing policy.
This surprises employers who assume any drug test screens for any drug. In reality, every panel is a defined list of target analytes, and benzodiazepines have never been part of the federally mandated panel that governs safety sensitive transportation testing. Employers outside DOT jurisdiction, including healthcare, manufacturing, and general workforce screening programs, have more flexibility to add benzodiazepine testing, but that flexibility comes with responsibility for understanding exactly what the chosen panel detects.
Prescription documentation and the Medical Review Officer
Diazepam is a Schedule IV controlled substance under the federal Controlled Substances Act schedule maintained by the Drug Enforcement Administration, meaning it has an accepted medical use along with a recognized potential for misuse relative to non scheduled medications. When a benzodiazepine screen returns non negative and confirmation identifies diazepam or its metabolites, a Medical Review Officer reviews the result before it reaches the employer. The MRO's role is to determine whether a legitimate medical explanation exists, generally a current, valid prescription, and to verify that documentation directly with the individual and, if needed, the prescribing provider. Employers should never interpret a lab result on their own or take employment action before MRO review is complete. This process protects both the integrity of the testing program and the rights of employees taking a lawfully prescribed medication.
What this means for testing programs
For employers, clinics, and testing programs building or reviewing a panel that includes benzodiazepines, a few practical points follow from the science:
- If detecting diazepam use is a program priority, confirm with the manufacturer or laboratory which benzodiazepine immunoassay is used and what its documented cutoff and cross reactivity are, since these vary by manufacturer and by which reference compound the assay is calibrated against.
- A non negative benzodiazepine screen does not identify which specific drug was used. Programs that need to distinguish diazepam from other benzodiazepines should route non negative results to LC-MS/MS or GC-MS confirmation.
- Benzodiazepines are not part of DOT's federally mandated five panel test under 49 CFR Part 40. Programs that want this coverage need to add it explicitly and document the addition in policy.
- Any confirmed positive result should go through Medical Review Officer review before any employment action, with the individual given the opportunity to provide valid prescription documentation.
Frequently asked questions
Does Valium always show up on a standard drug test?
Only if the panel includes benzodiazepine screening. The federal five panel test used for DOT safety sensitive testing does not include benzodiazepines at all, so diazepam would not appear on that specific panel. Many employer panels with 10 or more analytes do include a BZO screen, and diazepam and its active metabolites are generally detectable by those screens above the assay's cutoff.
How long does diazepam stay detectable in urine?
Diazepam has a long elimination half life, cited around 46 to 48 hours, and its active metabolite nordiazepam has a terminal half life reported up to 100 hours. Because detection depends on dose, frequency of use, and individual metabolism, no fixed number of days applies to everyone, and specific timing questions are best directed to a laboratory toxicologist or medical provider.
Is diazepam part of the federal five panel drug test?
No. The federally mandated panel referenced in 49 CFR 40.85 covers marijuana metabolites, cocaine metabolites, opioids, phencyclidine, and amphetamines and methamphetamine, along with MDMA and MDA. Benzodiazepines are not included and must be added separately if a testing program wants that coverage.
What happens if a benzodiazepine screen is positive but the person has a Valium prescription?
A Medical Review Officer reviews the confirmed result and any prescription documentation before the result is reported to the employer. A valid, current prescription for a legitimately prescribed medication is exactly the kind of information the MRO process exists to verify.
Can a diazepam screen tell the difference between Valium and other benzodiazepines?
Not on its own. The initial immunoassay reacts to a class of chemically similar compounds, not to diazepam specifically. Because diazepam metabolizes into oxazepam and temazepam, which are also prescribed on their own, confirmation testing by GC-MS or LC-MS/MS is needed to identify which specific drug and metabolites are actually present.
Is Valium a controlled substance?
Yes. Diazepam is listed as a Schedule IV controlled substance under the federal Controlled Substances Act, meaning it has an accepted medical use but also a recognized potential for misuse and dependence relative to non scheduled medications.
Related reading
- Benzodiazepine Drug Test: BZO Panel Detection Times and Gaps
- Does Klonopin Show Up on a Drug Test? Clonazepam and the Benzodiazepine Panel
Employers and clinics building or reviewing a benzodiazepine testing program can find reliable panels, including expanded options, in American Screening Corporation's drug test cups collection.
Sources
- Diazepam, StatPearls, NCBI Bookshelf (National Institutes of Health)
- Diazepam, MedlinePlus Drug Information (National Institutes of Health)
- Diazepam Oral Solution, FDA label via DailyMed (National Library of Medicine)
- 49 CFR 40.85, Cutoff Concentrations for Urine Drug Tests, Code of Federal Regulations (GovInfo, U.S. Government Publishing Office)
- Controlled Substances, Alphabetical Order, DEA Diversion Control Division (U.S. Department of Justice)
This article is general information only and is not legal or medical advice. Drug testing policies, panel selection, and prescription review should be handled with qualified legal counsel and a Medical Review Officer.
