Hair Drug Tests


Hair drug tests are one of the many different drug screening methods used to test for the presence of illegal drugs. These tests are extremely accurate and impossible to fool.

About Hair Drug Tests

Unlike urine, blood, and saliva drug tests, hair drug tests do not require a sample of bodily fluid from the individual being tested. This increasingly popular form of drug screening instead tests the shaft of a hair follicle.

Hair follicle testing can detect if drugs have been used within a 90-day period. Some tests can go back even further, detecting drug use that has occurred in the past six months.

Hair drug tests aren't anything new. They have been employed since the 1980s to test for the presence of illegal drugs. However, these tests are becoming more widely used due to the level of accuracy that can be achieved. Individuals who are subjected to the test cannot substitute samples or influence the results by changing habits a few days prior to taking the test.

When drugs are used, a residue becomes encased in the hair shaft. Evidence of drug use cannot be washed or bleached away. It will remain until the hair grows out or is removed. This means that short of shaving their head, individuals have no way to disguise the use of drugs.

Other advantages of hair tests over alternate methods of drug testing include:

  • A longer detection period
  • A sample collection that is non-intrusive
  • The ability to detect when a drug was used

Who Uses Hair Drug Tests?

Everyone from employers and courts to schools and parents use hair drug tests to make sure that individuals are not abusing drugs like cocaine, marijuana, opiates, and amphetamines. Because many court systems use hair drug tests as part of parole and probation programs, the results from this sort of testing are often admissible in court, as well as in agency and arbitrary hearings. Some of the largest police departments in the U.S. also routinely utilize this method of drug testing.

An increasing number of employers are turning to hair testing, as it is now considered to be the most effective method of pre-employment drug testing available. Studies performed by The National Institute of Justice have shown that hair tests are better at detecting long-term drug use than urine tests.


Though hair drug tests cost more initially--the average lab test costs between $100 and $150--they can be a more cost effective method of testing than urine or saliva tests. This is because the costs of drug abuse can add up in a long-term scenario.

For example, if a corporation were to hire an individual who abuses drugs, but managed to pass a urine test, the corporation may be setting themselves up for costly problems later on. The individual who passed the test might someday abuse drugs on the job or cause an accident that results in a lawsuit.

Government studies estimate that one out of every six workers within the U.S. has a drug problem. This is a serious concern for employers when you consider some of the facts associated with drug abusers in the workplace:

  • Employees who use drugs are absent more often than employees who don't use drugs.
  • Employees who abuse drugs cost companies approximately 300 percent more in medical costs than employees who don't abuse drugs.
  • Drug addicts are often not very productive when in the workplace.
Was this page useful?
Related & Popular
Hair Drug Tests