What is a drug test?

A drug test is a chemical analysis that detects potential drug consumption through examination of a submitted biological sample. This sample is often urine but can also be blood, breath, saliva, sweat, or hair samples. Hair testing is increasingly used because it can detect long term use. A drug test reveals the presence of the drug itself or at least one of its metabolites.

Drug tests are generally done as a screening test first (this can be done as an on-site test or at a laboratory) and then sent to a laboratory for confirmation testing if an initial positive result is returned or if there is a problem with the submitted sample. On-site screening tests are often referred to as POC, or point of collection, tests and can be done quickly. They are often named based on the number of drugs or drug metabolites they can detect. For example, a 5 panel drug test tests for 5 drug classes and a 10 panel drug test looks for 10 drug classes. Confirmation tests are usually completed in certified laboratories using equipment such as a gas chromatograph/mass spectrometer.

The illegal drugs that are generally screened are: amphetamines, cocaine, opiates, phencyclidine, cannabinoids, hallucinogens. Prescription drugs can also be tested for illicit use: morphine, barbiturates, benzodiazepines, methaqualone, methadone, and propoxyphene. Other substances such as inhalants and anabolic steroids can also be tested.

In the workplace, employers have the right in most jurisdictions to test their employees to detect illegal drugs use and alcohol abuse in order to try to maintain a safe workplace. When drug testing is done depends on regulations from agencies such as the DOT or from written company guidelines. Some common times an employee may be drug tested includes before formal employment, randomly, when there is a reasonable suspicion, after an accident, and/or after a suspension of the employee for drug use.

When an employee is tested positive, he/she can often be fired “for cause” and may lose his/her right for some benefits such as unemployment insurance, or worker’s compensation. Alternately, a company may insist the employee complete a counseling program and test for drugs again or may be placed on a probation period with supervision. Again, regulatory agencies such as the DOT and a company's written drug and alcohol policy should spell out the exact procedure for the company and the situation.