The What And How Of Hair Follicle Drug Tests: Facts And Myths

Hair Follicle Drug Test

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Last Updated on August 21, 2023 by Steal the Style

Where and Why Are Hair Tests Conducted?

Many companies do a hair follicle drug test along with a blood and urine test to weigh in on hiring decisions, custody decisions, or to screen illicit drug use.

From a  trial of brief drug use in New Mexico, overall concordance between hair testing and self-report was 57.5% (marijuana), 86.5% (cocaine), 85.8% (amphetamines), and 74.3% (opioids)

All in all, a person may need to undergo drug testing for employment, legal, or medical purposes.

Testing Drugs Through Hair

Hair follicle testing can take place in a lab or in a hospital setting. It can even take place in your workplace. One may perform the test using a kit that’s then mailed to a laboratory. If anyone wants to do it in their house itself, they can even order the Home Follicle test setup.

The collector will cut between 100 and 120 hairs from the crown of your head. Hair can be collected from different parts to avoid a gap.

It confirms a positive drug test within 72 hours. All non-negative tests undergo a second round, called gas chromatography/mass spectrometry (GC/MS). It confirms a positive test result while also identifying the specific drugs used.

Hair drug testing goes back much further than urine drug testing. As a matter of fact, when you ingest a drug, the drug indicators can go into a strand of hair and stay there forever. If you think about it, your hair grows at an average of 0.5 inches a month.

Therefore, if your hair is 18 inches long, and you test at the end of the hair strand, drugs could be detected in your hair for the next 3 years. No need to worry though! There is only one standard for this test: 1.5 inches of hair, cut from the root. This will detect your results approximately from the 2 previous months.

Myths About Hair Follicle Drug Testing

Myth 1: Hair follicle drug tests can detect drug use far into the past.

Fact: Drug tests on hair typically cover a 90-day period. A standard test uses the first 1.5-2 inches of hair- Not the entire strand. For job testing and other standard cases, you only need to worry about the top 2-3 inches from the scalp.

Myth 2: If I shave my head, the Lab can’t conduct a hair follicle drug test.

Fact: If they can’t obtain enough of a sample from your head, hair can be tested from your chest, arms, and legs. If you don’t have any hair on your body, however, they can’t conduct the test.

Myth 3: I can use a special shampoo to wash evidence of drugs out of my hair.

Fact: The Hair Follicle test penetrates into the core of your hair. So, even though the outer layer can be cleansed off drugs – the inner layers can’t be. No shampoo in the market can completely erase drugs off your hair, except Aloe Rid old formula.

Myth 4: Secondhand smoke can cause you to fail a hair drug test.

Fact: Will you come out positive in a hair follicle drug test if you haven’t actually smoked?

Secondhand smoke means “passive exposure.” This means, using marijuana as an example, you’re not actually inhaling any amount of THC — the active component in marijuana that gets you high — from the source.

The levels taken in have to be past a certain threshold to get detected. If it’s not beyond that threshold, then the result will be negative. And passive exposure to some has found to be under the minimum threshold.

So if you take a hair drug test after being around Marijuana, it won’t evidently show in the test.

For further information on how to pass a hair follicle drug test, you can refer to various Internet sites informing you such as

Facts About Hair Follicle Drug Test

The Hair Follicle Test can detect any alcohol or drugs in the body. The scope of drugs that can be examined using it is only increasing. Below is the expanding list of drugs that can be screened via hair follicle:

  • Cocaine
  • Marijuana (THC, cannabinoids)
  • Amphetamines (including methamphetamines)
  • Basic Opiates (heroin, morphine, codeine)
  • Expanded Opiates (hydrocodone, oxycodone)
  • PCP (Angel Dust)
  • Benzodiazepines (Xanax)
  • Synthetic Marijuana
  • Ketamine
  • Buprenorphine (Suboxone)
  • Zolpidem (Ambien)
  • Alcohol


The hair follicle drug test is fail-proof and highly helpful for detecting drug intake. Precisely because it is dependent on hair. And with a mere inch of hair, it can trace back the components present in the blood.

Hair tests are also efficient when used to draw comparative test results, to find out when a drug was used, how long it was used for, or to determine if drug use was discontinued.

And thus, it is an extremely potent testing mechanism.

The What And How Of Hair Follicle Drug Tests