Drug Test
A drug test is a procedure done to look for substances in the body samples of hair, urine, saliva and the other bodily fluids that can be used to screen for drugs. Typically, it is done to determine the presence of most-commonly abused drugs in the body which include cocaine, marijuana, heroin, methadone, antidepressants and other drugs.
Who Conducts Drug Tests?
There are two types of drug screenings: federally regulated and non-federally regulated drug testing. Federal tests are done on federal employees, professional drivers, especially for oil and gas transport corporations and other government employees.
Health care workers and those enrolled in drug rehab programs are also subjected to regular screenings. Tests may also be conducted in schools where drug use is being suspected in students.
Onsite and Laboratory Screening
A drug test may be done onsite or in laboratories. Onsite drug examinations are done using portable testing kits and are typically the mode of drug screening done in hospitals and rehab centers. Drug screening kits can screen for multiple drugs in a matter of minutes. However, it is necessary to obtain a laboratory result in the case of a positive result and when action is needed against the donor. This often happens during employee or rehab drug examination, where a positive result will negatively affect the donor's employment or rehabilitation status. An alcohol test can also be done onsite using a breath analyzer. This type of test is usually done by highway patrolmen on motorists suspected of driving under the influence of alcohol.
Laboratory drug examinations have the advantage of having the screening phase and the confirmation phase both done in one place, one after the other. The main disadvantage is the time lost in shipping the samples from the place of origin to the lab. A laboratory drug exam is also more expensive than on-site drug test kits and usually requires about 24 hours for the screening results and 2-5 days for confirmation of results.
Both onsite testing kits and lab tests typically use urine samples for testing. A urine test is the most common type of drug screening done today partly because it is non-invasive and easy to obtain.
Other Tests
Other kinds of drug test include hair drug screenings and oral or saliva wipes. Hair testing uses hair strands to test for longer periods of drug use, as hair tends to keep traces of drugs for as long as the hair has been growing. Larger sections of hair can be tested for an overall image of the drug history. This process is more time-consuming than urine or saliva testing, however, since hair needs to be fixed before it can be tested. Oral or saliva tests are done as non-invasively as possible but there are screening agencies that may not have internationally-standardized cut-off levels similar to those of urine tests.