Drug Test Result Time

TEST SENSITIVITY

The Substance Abuse and Mental Health Services Association (SAMHSA) provides guidelines for what qualifies as a positive drug test. If a test does not give results higher than the guidelines, it does not qualify as a "positive" test. If an immunoassay test gives positive results, a second Gas Chromatography test must also give positive results before a result of "positive" is announced. The following chart shows the guidelines by substance.

SUBSTANCE	IMMUNOASSAY	GC / MS
Cannabis	50 ng/ml	15 ng/ml
Cocaine	300 ng/ml	150 ng/ml
Opiates	300 ng/ml	300 ng/ml
Amphetamines	1000 ng/ml	500 ng/ml
PCP	25 ng/ml	25 ng/ml

Some companies are getting around these guidelines by reporting the levels found without categorizing them as a "positive" or "negative" test. This seems to be a problem primarily with mail-in home tests rather than corporate testing.

DETECTION PERIODS

The following chart gives approximate detection periods for each substance by test type. The ranges depend on amount and frequency of use, metabolic rate, body mass, age, overall health, drug tolerance, and urine pH:

SUBSTANCE	BLOOD	SALIVA	SWEAT	URINE	HAIR
Alcohol	unknown	unknown	unknown	6-24 hrs	n/a
Amphetamine	unknown	3 days	unknown	1-4 days	up to 90 days
Barbiturates	unknown	unknown	unknown	1-21 days	unknown
Benzodiazepines	unknown	unknown	unknown	1-42 days	unknown
Cannabis (single use)	2-3 days	14 hrs	unknown	2-3 days	up to 90 days
Cannabis (habitual use)	2 weeks	14 hrs	unknown	up to 12 wks	up to 90 days
Cocaine	unknown	1 day	unknown	4-5 days	up to 90 days
Codeine/Morphine	unknown	7-21 hrs	unknown	2-4 days	up to 90 days
Heroin	unknown	unknown	unknown	8 hrs	up to 90 days
Methamphetamine	1-3 days	unknown	unknown	3-5 days	up to 90 days
PCP	1-3 days	3 days	unknown	3-7 days	up to 90 days