Naloxone Drug Test Guide: Panels, Detection Windows & More

Evidence-based answer reviewed against SAMHSA cutoffs and FDA assay documentation · Updated September 2026

Quick answer: Opioid antagonist (emergency reversal agent) — not included on the federal 5-panel. Urine detects it roughly not tested / no interference; hair archives ~90 days; saliva and blood track only recent use. Never screened on any standard or expanded employment panel.

Overview

This guide covers everything verifiable about how testing handles Naloxone (opioid reversal agent) (also searched as: narcan, evzio, opioid antagonist): which panels include it, detection windows across specimens, cutoff levels, false-positive risks, and legitimate prescription handling.

Panel membership

PanelNaloxone status
5-Panel❌ Not included
10-Panel❌ Not included
12-Panel❌ Not included
DOT 5-panel (safety-sensitive)❌ Not included

Detection windows

Ranges reflect occasional-to-heavy use patterns from FDA device inserts and SAMHSA-certified lab conventions.
Test typeTypical Naloxone detection window
Urineany: not tested / no interference
Saliva (Mouth Swab)any: n/a
Hair Folliclesn/a
Bloodany: n/a

Cutoff levels

Never screened on any standard or expanded employment panel.

Cutoffs exist to separate real use from noise — dietary exposure, passive contact and legacy medications stay below them by design. Screen-above-cutoff results still require mass-spec confirmation before reporting.

Deep-dive facts

Naloxone is an opioid antagonist used to reverse opioid overdoses — it is not a drug of abuse and produces no intoxication. It appears on no standard or expanded drug panel, and it does not cause positives for opioids or any other screened drug.

If you administered naloxone to someone else (or received it yourself during an overdose), it will not show up on your own drug test. The only interaction to know about is medical, not testing: naloxone can precipitate withdrawal in opioid-dependent people.

The 'does Narcan show up on a drug test' question is common because people carry or administer it in emergencies. The answer is no: no panel screens for it, and it has no cross-reactivity with any standard immunoassay.

False positives & cross-reactivity

  • None — naloxone has no documented cross-reactivity with any standard drug immunoassay.
Source basis: Brahm NC et al., Mayo Clinic Proceedings 2008;83(1):66–76 plus FDA assay inserts. GC–MS/LC–MS confirmation eliminates these artifacts.
Screen flaggedDocumented cross-reactants (immunoassay tier only)
AmphetaminesBupropion (bupropion), trazodone, phentermine, pseudoephedrine, labetalol, promethazine, methylphenidate
PCPDextromethorphan (dextromethorphan cough syrup), diphenhydramine (diphenhydramine), doxylamine (multi-symptom cold remedies), tramadol, venlafaxine (venlafaxine), ketamine
OpiatesPoppy seeds (true positive), quinine, dextromethorphan, ofloxacin/levofloxacin, rifampin
BenzodiazepinesSertraline (sertraline), oxaprozin (case reports)
MethadoneDiphenhydramine, doxylamine, verapamil, quetiapine (quetiapine), clomipramine
Tricyclics (TCA)Cyclobenzaprine (cyclobenzaprine), hydroxyzine, carbamazepine, diphenhydramine
Cannabinoids (THC)Efavirenz, pantoprazole (isolated reports); dronabinol/dronabinol = true positive

Legal status note

Rx/emergency medication; not a controlled substance.

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Medical disclaimer: DrugPanels provides educational information about laboratory drug testing and does not offer medical advice, diagnosis, or treatment. Detection windows are population ranges — individual results vary with metabolism, dose, frequency and health status. Never stop prescribed medication to pass a test without talking to your prescriber. Affiliate disclosure: some links on this page are affiliate links; if you order through them we may earn a commission at no additional cost to you.

People also ask

Does Naloxone Show up on a Drug Test?

No — Naloxone is absent from standard drug panels. Full guide →

Can Narcan Cause a Positive Drug Test?

Can Naloxone trigger a false positive? Cross-reactivity evidence, confirmation testing, and how to clear your name with the MRO. Full guide →

Naloxone Drug Test Guide: Panels, Detection Windows & More?

Complete Naloxone drug test guide: which panels detect it, urine/hair/saliva/blood detection windows, cutoff levels and prescription verification. Full guide →

How Long Does Naloxone Stay in Urine?

How long Naloxone stays detectable in urine — urine, hair, saliva & blood windows explained with cutoffs. Full guide →

How accurate are drug tests?

Lab-based immunoassay screens agree with confirmation testing ~97% of the time; confirmed GC–MS results are considered definitive. Home kits trade legal defensibility for convenience.

Do prescriptions count against me?

No — verified prescriptions report as negative through the Medical Review Officer. Declare medications at collection and answer the follow-up call.

Sources & further reading

  • SAMHSA — Mandatory Guidelines for Federal Workplace Drug Testing Programs (cutoffs, MRO process)
  • DOT — 49 CFR Part 40 procedures for transportation workplace testing
  • Brahm NC et al., Mayo Clinic Proceedings 2008;83(1):66–76 — false-positive cross-reactivity reference
  • FDA — drug-of-abuse test device labeling (detection window conventions)