Drug testing is performed to detect the presence of drugs (typically illegal drugs) in the body. There are a variety of reasons why an individual may be asked to undergo a drug test. Employers may screen candidates for drug use prior to hiring them, or screen employees periodically to test for sobriety. Law enforcement officials may test individuals who appear to be under the influence, or to make sure that those on probation or parole are sticking with the program. Parents may also test their children to find out if they are using.

Drug tests may be administered to check for the use of cannabis, cocaine, heroin, speed, PCP, alcohol or other drugs.http://www.erowid.org/psychoactives/testing/testing_info1.shtml#sensitivity

• Urine tests: Urine tests are the most commonly used drug tests, as they are cost effective and also good at detecting infrequent drug use.http://jobsearchtech.about.com/od/laborlaws/l/aa090301_3.htm
• Blood tests: A blood test is the most accurate type of drug test. However, it is expensive to do and is not as simple to perform comfortably as a urine test. This type of drug test is not permitted in the federal drug testing program.http://jobsearchtech.about.com/od/laborlaws/l/aa090301_3.htm
• Hair tests: Hair tests may be used to track long term drug use. These tests will not detect recent drug use, but can often help establish when drugs have been used in the past, as well as when someone quit.http://www.erowid.org/psychoactives/testing/testing_info1.shtml#sensitivity
• Saliva tests: These tests cost more than urine tests, but not as much as blood or hair tests. They are primarily used to track recent drug use.http://www.erowid.org/psychoactives/testing/testing_info1.shtml#sensitivity

The content on this page is not a substitute for professional medical advice. Please contact your doctor or pharmacist before using the information here.