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Drug Test Detection Period

How to understand drug detection periods

Their administration’s technical competency is very thorough, and their understanding of their system is outstanding.
—Mobile Health Client

Did you know that the detection period for drugs during a drug test varies greatly?  An infrequent smoker of marijuana might pass a urine drug test 3 weeks after last use, but a regular smoker will test positive for up to 2 months after last use! Cocaine users have even a shorter detection time of only a few days. The test specimen, individual, and drug tested are all important variables to consider when evaluating a drug test result.

The specimen of choice makes a big difference in the detection period. Popular specimens include urine, blood, hair, and saliva. Most businesses and organizations choose urine drug testing due to price and reliability.  Saliva testing is second in popularity due to practicality and reduced risk of adulteration of the specimen sample.

Urine drug tests for marijuana detects usage up to 2 months after last use. This is because the urine test checks for THC-COOH, a non-psychoactive fat-soluble metabolite that is released from the body slowly. This metabolite is usually stored in the individual’s body fat, and the person’s metabolism and body fat content will affect the detection time frame.

Individuals who smoke marijuana more regularly will have higher deposits of THC-COOH, and allow for a longer testing window. Likewise, users who have higher body fat will test positive for a longer period of time due to more fat for THC-COOH to attach to.

Saliva or oral drug testing has even a shorter detection period. Most saliva drug tests can detect marijuana usage within a few hours up to 3 days. This testing method is preferred if recent usage is crucial to the test, but not recommended for surveying long term use.

Besides marijuana, most other drugs tested in a urine drug test will have a limited detection time of less than a week; with the exception of methadone and PCP which can be detected up to 30 days after last use. Saliva and blood testing are also limited to a few days after use.

For longer term testing, employers can consider using hair testing. Like saliva testing, hair testing is less susceptible to adulterants and can detect most drug use up to 90 days after last use. This includes hard to detect drugs such as cocaine and methamphetamine.

Mobile Health has 6 medical centers dedicated to employee screening procedures including drug testing. Although most employers use urine drug testing, your account manager can discuss saliva, blood, and hair testing as possible options for your business.