Drug testing detects the presence of drugs and drug metabolites using cutoff levels to determine whether a specimen tests positive or negative for the use of a specific drug. A cutoff level is a threshold. If the concentration of a drug is above the cutoff, it is a positive result. If it is below, it is negative.

Note that a negative result does not mean “no drugs.” It merely means that if any drugs are present, they are below the cutoff level.

Screening level vs. confirmation level

In workplace drug testing, the standard process involves potentially two steps: an initial screen, followed by a confirmation test, but only if the screening test was non-negative.

The initial test is a quick screen that separates negative specimens from further consideration. The confirmation test uses gas/liquid chromatography-mass spectrometry (e.g., GC-MS, LC-MS/MS) or a similar method, which can specifically identify and quantify the drug/metabolite in the specimen.

What does ng/mL and pg/mg mean?

Cutoff levels are expressed in nanograms (ng) per milliliter (mL) for urine drug testing and oral fluid drug testing or picograms (pg) per milligram (mg) for hair drug testing. These denote the concentration level of the drug metabolite.

Each specimen type and drug tested has a different detection window. As a broad generalization, a hair test will detect up to 90 days of use (but not the most recent week). Oral fluid can detect drugs from a few minutes ago up to 3 or 4 days for some drugs. And urine is good for a few hours up to 4 days for most drugs, but 30 days or more for heavy marijuana use.

Federal drug testing cutoff levels

Cutoff levels for federally regulated drug testing programs are established based on mandatory guidelines set by U.S. Department of Health and Human Services (HHS). The US Department of Transportation follows the Federal guidelines. Rule 49 CFR Part 40 for details on testing and procedures.

Non-Federal (aka Non-DOT) drug testing cutoff levels

Many non-regulated employers mirror the cutoff levels established by the government while others customize their drug testing panels to be more sensitive to certain drugs based upon their program needs and unique workforce. Mirroring is generally good practice as it keeps the program defensible.

Lab-based urine drug test common cutoff levels

SubstanceScreen cutoffConfirmation cutoff
Amphetamines500 ng/mL250 ng/mL
Cocaine metabolites 150 ng/mL100 ng/mL
Marijuana metabolites50 ng/mL15 ng/mL
MDA-analogues500 ng/mL250 ng/mL
Opiates2000 ng/mL2000 ng/mL
6-Acetylmorphine (6-AM)10 ng/mL10 ng/mL
Opiates (semi-synthetic)300 ng/mL100 ng/mL
Oxycodones100 ng/mL 100 ng/mL
Phencyclidine (PCP) 25 ng/mL25 ng/mL

Urine specimen 5-panel drug test cutoff levels

SubstanceScreen cutoffConfirmation cutoff
Amphetamines1000 ng/mL500 ng/mL
Cocaine metabolites300 ng/mL150 ng/mL
Marijuana metabolites50 ng/mL15 ng/mL
Opiates2000 ng/mL2000 ng/mL
Phencyclidine (PCP)25 ng/mL25 ng/mL

Urine specimen 9-panel drug test cutoff levels

SubstanceScreen cutoffConfirmation cutoff
Amphetamines1000 ng/mL500 ng/mL
Cocaine metabolites300 ng/mL150 ng/mL
Marijuana metabolites50 ng/mL15 ng/mL
Opiates2000 ng/mL2000 ng/mL
Phencyclidine (PCP)25 ng/mL25 ng/mL
Barbiturates300 ng/mL300 ng/mL
Benzodiazepines300 ng/mL200 ng/mL
Methadone300 ng/mL200 ng/mL
Propoxyphene300 ng/mL200 ng/mL

Instant urine drug test common cutoff levels – Note that an instant test (aka “rapid” or “POCT”) is a screening test, and non-negative results need to be confirmed by laboratory testing.

Instant test cutoff levels can vary tremendously from one manufacturer to another.

SubstanceScreen cutoff
Amphetamines1000 ng/mL
Methamphetamines1000 ng/mL
Cocaine/metabolite300 ng/mL
THC/metabolite50 ng/mL
Opiates2000 ng/mL
Phencyclidine (PCP)25 ng/mL

Oral fluid drug test common cutoff levels

SubstanceScreen cutoffConfirmation cutoff
Amphetamine150 ng/mL120 ng/mL
Cocaine metabolites15 ng/mL6 ng/mL
Marijuana3 ng/mL1.5 ng/mL
Methamphetamines120 ng/mL120 ng/mL
Opiates30 ng/mL30 ng/mL
Oxycodones30 ng/mL30 ng/mL
Phencyclidine (PCP)3 ng/mL1.5 ng/mL

Hair drug test common cutoff levels

DrugScreen cutoffConfirmation cutoff
Methamphetamines500 pg/mg500 pg/mg
MDMA500 pg/mg500 pg/mg
Amphetamine500 pg/mg500 pg/mg
Cocaine/metabolites500 pg/mg500 pg/mg
Benzoylecgonine500 pg/mg500 pg/mg
Marijuana metabolite1.0 pg/mg0.1 pg/mg
Opiates (MOR &/OR HYM)200 pg/mg200 pg/mg
Opiates (COD &/OR HYC)200 pg/mg200 pg/mg
6‐Acetylmorphine (6‐AM)200 pg/mg200 pg/mg
Oxycodone200 pg/mg200 pg/mg
Oxymorphone200 pg/mg200 pg/mg
Phencyclidine (PCP)300 pg/mg300 pg/mg