Drug test cutoff levels are the minimum concentrations of a substance that must appear in a specimen before the laboratory reports the result as positive. For federal workplace and DOT-regulated testing, urine cutoffs run from 1 ng/mL for fentanyl at the low end to 2,000 ng/mL for codeine and morphine at the high end. Anything below the cutoff is reported as negative, even if trace amounts are technically present. The thresholds exist because at the nanogram scale (one-billionth of a gram), passive exposure, food, and medications can leave measurable traces that have nothing to do with drug use.
Federal Urine Cutoff Levels
The Substance Abuse and Mental Health Services Administration (SAMHSA) publishes the Mandatory Guidelines for Federal Workplace Drug Testing Programs. Every federal agency and every DOT-regulated employer follows these numbers. Each drug has a screening cutoff (the first-round immunoassay) and a confirmation cutoff (the second-round mass spectrometry test).
Marijuana (THC)
Screening cutoff: 50 ng/mL. Confirmation cutoff: 15 ng/mL, targeting the THCA metabolite. The wide gap reflects the different jobs of the two tests: the screen is a broad filter, and confirmation homes in on a specific metabolite at a lower concentration.
Cocaine
Screening at 150 ng/mL and confirmation at 100 ng/mL, both for the metabolite benzoylecgonine.
Amphetamines and MDMA
Amphetamine, methamphetamine, MDMA, and MDA share a 500 ng/mL screening cutoff. Confirmation is 250 ng/mL for each individual substance.
Opioids
Opioid testing covers three separate groups:
- Codeine and morphine: screening at 2,000 ng/mL. Codeine confirmation stays at 2,000 ng/mL, but morphine confirmation was raised to 4,000 ng/mL under the revised guidelines. The higher morphine bar reduces the chance that a codeine user, who metabolizes some of the drug into morphine, gets flagged incorrectly.
- Hydrocodone and hydromorphone: 300 ng/mL screening, 100 ng/mL confirmation for each.
- Oxycodone and oxymorphone: 100 ng/mL screening, 100 ng/mL confirmation for each.
Heroin is detected through its unique metabolite 6-acetylmorphine (6-AM), at 10 ng/mL for both screening and confirmation.
Phencyclidine (PCP)
Both screening and confirmation are set at 25 ng/mL.
Fentanyl
Starting July 7, 2025, federal agencies can include fentanyl in their testing panels. The screening cutoff is 1 ng/mL, with confirmation at 1 ng/mL for both fentanyl and its metabolite norfentanyl. That 1 ng/mL threshold is the lowest on the entire federal panel, reflecting fentanyl’s potency and the small amounts that produce detectable metabolites.
Federal Oral Fluid Cutoff Levels
Oral fluid (saliva) testing is authorized as an alternative to urine for federal and DOT-regulated programs. Saliva cutoffs run much lower than urine cutoffs because drugs appear in oral fluid at smaller concentrations and for shorter windows. Saliva is better at detecting very recent use; urine catches metabolites over a longer period.
- Marijuana (THC): 4 ng/mL screen, 2 ng/mL confirmation.
- Cocaine and benzoylecgonine: 15 ng/mL screen, 8 ng/mL confirmation.
- Codeine and morphine: 30 ng/mL screen, 15 ng/mL confirmation.
- Hydrocodone and hydromorphone: 30 ng/mL screen, 15 ng/mL confirmation.
- Oxycodone and oxymorphone: 30 ng/mL screen, 15 ng/mL confirmation.
- 6-Acetylmorphine (heroin): 4 ng/mL screen, 2 ng/mL confirmation.
- PCP: 10 ng/mL screen, 10 ng/mL confirmation.
- Amphetamine and methamphetamine: 50 ng/mL screen, 25 ng/mL confirmation.
- MDMA and MDA: 50 ng/mL screen, 25 ng/mL confirmation.
- Fentanyl: 4 ng/mL screen, 1 ng/mL confirmation.
All oral fluid cutoffs are based on undiluted (neat) oral fluid.
Hair Testing
Federal programs under SAMHSA do not currently authorize hair testing, so there are no mandatory federal cutoffs for this specimen type. Many private employers still use hair testing for pre-employment screening because hair captures roughly 90 days of use history. Without a federal standard, cutoffs vary by laboratory. A widely used set of thresholds from major commercial labs:
- Marijuana metabolite: screen at 1 pg/mg, confirm at 0.1 pg/mg.
- Cocaine and benzoylecgonine: 500 pg/mg for both screen and confirmation.
- Opiates (morphine, codeine, 6-AM): 200 pg/mg for both.
- Amphetamines including MDMA: 500 pg/mg for both.
- PCP: 300 pg/mg for both.
Hair testing uses picograms per milligram rather than nanograms per milliliter, so the numbers don’t compare directly with urine or oral fluid cutoffs. Hair generally has a much longer detection window but does not reliably detect use within the most recent week or two, since the drug needs time to grow out from the scalp.
Why Every Drug Has Two Cutoffs
Every standard drug test uses two rounds. The first is an immunoassay screen, a rapid antibody-based technique that flags samples at or above the screening cutoff for a whole class of drugs. If your sample is below that threshold, the result is negative and the process stops there.
Samples that screen positive move to a confirmation test using gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). These instruments identify individual molecules by breaking them into fragments with unique patterns. Confirmation cutoffs are usually equal to or lower than screening cutoffs, so a drug flagged in round one can be verified with greater precision in round two. A positive screen followed by a below-cutoff confirmation is reported as negative.
The Medical Review Officer Step
In federal and DOT-regulated programs, a confirmed positive still isn’t final until a Medical Review Officer (MRO) reviews it. The MRO is a licensed physician who contacts you directly and gives you the chance to present a legitimate medical explanation, such as a current prescription, before the result is verified. You carry the burden of presenting that evidence during the interview, and the MRO takes reasonable steps to verify the prescription’s authenticity. If you decline the interview or fail to respond within 72 hours after your employer notifies you to call the MRO, the result is verified as positive by default.
What Can Push You Over a Screening Cutoff Without Drug Use
The two-stage process catches most false positives, but the immunoassay screen is where the trouble starts. Immunoassays target a class of chemicals rather than individual molecules, so structurally similar compounds can trigger a positive screen that later confirmation clears.
CBD and Delta-8 Products
Hemp-derived CBD is legal at the federal level, but many products contain enough residual THC to push you past the 50 ng/mL marijuana screening cutoff. In one study of 80 unregulated CBD products, 37 percent contained enough THC to exceed the daily intake level associated with positive tests. Products labeled “THC-Free” are not reliable either; roughly one in four tested products with that label contained detectable THC. Delta-8 THC products carry a similar risk because they metabolize into compounds that cross-react on marijuana immunoassays. Under federal testing rules, a positive result from CBD or hemp use is not treated as a legitimate medical explanation.
Common Medications
Several everyday medications can trigger false-positive screens. Pseudoephedrine and other decongestants have flagged amphetamine screens. Antidepressants including bupropion and trazodone have been linked to false amphetamine positives. Dextromethorphan, found in many cough syrups, can flag both opioid and PCP screens. Proton pump inhibitors and ibuprofen have caused false cannabinoid results in some immunoassay formats. This is one reason confirmation testing and the MRO interview matter: a prescription or an identifiable over-the-counter product can explain the screen and stop a wrongful positive.
How Cutoffs Translate Into Detection Windows
Cutoff levels and detection windows work together. A lower cutoff extends the window; a higher one shortens it. At the standard federal urine cutoffs:
- Marijuana: about 3 to 4 days for a single use at 50 ng/mL. Daily users may test positive for 5 to 10 days after stopping; chronic heavy users can remain detectable for up to 30 days.
- Cocaine: 1 to 3 days. A single use clears in roughly a day; several days of consecutive use extends detection to about 3 days after the last dose.
- Amphetamines and MDMA: 2 to 4 days.
- Opioids (codeine, morphine): 1 to 3 days.
- PCP: 2 to 7 days for a single use, up to 30 days with chronic use.
These windows shift with individual metabolism, body composition, hydration, frequency of use, and dose. Marijuana is the outlier because THC is fat-soluble and accumulates in tissue, which produces the widest gap between occasional and heavy users.