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Schools, courts, hospitals and workplaces often require drug testing. Many employers require a drug test before you can be hired or start a new job.

Drug tests are most often done using a urine drug test or blood sample. However, in some cases, a strand of hair may be used to test for drugs. Hair can provide a wider window to detect drug use. Hair tests can be used to detect drugs that have been used in the past one to three months.

How does the hair follicle drug test work?

Hair follicle testing analyzes for illegal drugs within the hair shaft. It measures drug molecules entrapped in hair. A hair test covers a period of months, so a drug user cannot avoid positive test results by simply stopping drug use for a few days.

What type of drugs can be detected in a hair test?

A hair follicle drug test typically screens for:

  • Cocaine
  • Marijuana (also called THC)
  • Opiates (narcotics), such as heroin, codeine, morphine, oxycodone, hydrocodone
  • Methamphetamines, amphetamines, crystal meth
  • Phencyclidine, or PCP

What should you expect with a hair follicle drug test?

Your healthcare provider will cut a small lock of hair, about the width of a shoelace tip, close to the scalp. The hair must be at least 1.5 inch long per strand to be analyzed. It’s typical to snip a lock of hair at the back of the head just below the crown, so it’s not detectable. Although it is more common to use head hair, hair can be used from the chest, leg or armpit.

If you are required to take a hair follicle drug test by your prospective or present employer, contact the nearest CareNow® urgent care clinic. You can minimize your wait time with our Web Check-In®.

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