Hair Follicle Drug Testing | The Myths

Hair follicle testing is one of the most fascinating tests we use to determine drug use. Once drugs are ingested and enter the blood stream, traces of this blood nourish the hair follicles, and provide those of us who perform drug tests a great way to get an accurate read on drug usage. The blood enters the very core of the hair follicle, and provides for an extremely accurate test.


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What Drugs can Hair Follicle Testing Detect?

Drug testing hair follicles has been proven to detect the following drugs:

  • Marijuana
  • Opiates
  • Methamphetamines
  • Ecstasy
  • Cocaine
  • PCP
  • Alcohol

Myths about Hair Follicle Drug Testing

There are several myths out there when it comes to drug testing hair follicles. Here are some common misconceptions of hair follicle drug testing:

Myth: You Can Wash Out … or Dye … the Evidence of Drug Use

With hair follicle drug testing, there is no way to rid the evidence. Blood will enter the hair shaft and reside on the very inside part of the hair. Because of this, no special shampoo, hair dye nor bleach will work to remove the evidence of drug use in the hair.

Myth: Hair Follicle Testing isn’t as Effective as Urine Testing

Contrary to some popular beliefs, hair follicle testing is actually much more effective than urine tests. In a urine test, you will only detect substances that have traces in the blood stream. With a hair test, you can still pick up traces of drug use even 90 days later, to a year. A hair follicle test is a great way to detect if drugs have been used in the past 30 days, up to a year.

Myth: Only Head Hair may be Used in a Drug Test

Hair from any area of the body may be used for drug testing. Some of the other common areas to gather hair for drug testing include underarms, legs and arms. At least a half-inch of hair is required for a proper drug test (this is the average length hair grows in a month). While hair from any part of the body can indicate if a drug has been ingested (within the year!), it’s only guaranteed that head hair will determine if drugs have been used in 90 days.

Myth: One Hair is Enough to Test

To perform an accurate follicle drug test, you need approximately 100-120 strands of hair, and at least a half of an inch. That rounds out to be the approximate diameter of a pen or pencil. You don’t have to pull your hair out in order to provide a test; simply find a small spot near the back of your head and cut a section of hair close to your scalp.

Myth: You can Test Hair from a Hairbrush

In the same way that one hair isn’t enough, a drug test won’t be accurate if using hair from a hair brush. First, you don’t know how old the hairs are that reside in the brush. Next, a good test depends on all of the root ends being together. With hair from a hairbrush, you often have no idea which end came from your scalp. It’s best advised that the person being drug tested with a hair follicle drug test know that it’s coming, so that they are prepared to have a small section of hair cut and used for testing.

Stay tuned for more information on hair follicle drug testing.

Have specific questions about drugs picked up in a hair follicle drug test? Let us know!

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