Hair Follicle Drug Test: Detection Time & Cutoff Levels

Testing hair follicles have proven effective to detect a variety of drugs, even if only small doses were used. Knowing the ins and outs of the hair drug testing can help you get a clear idea about what the tests do and how they do it.


Clear Results

When compared ещ the analysis of urine, hair tests show better results when looking for cocaine, opiates, PCP, and methamphetamines. Meanwhile, urine test for marijuana is just as effective as the hair follicle drug test detection.


The List of Drugs Detected by Hair Follicle Drug Test

  • Cocaine
  • Marijuana
  • Codeine
  • Morphine
  • Methamphetamine
  • Phencyclidine (PCP)


From Using to Hair Follicles Testing

How do the drugs end up in the hair follicles? The substances get into the blood system and enter the hair follicle cells together with nourishing ingredients. The cells keep growing and trap the molecules inside. As a result, the drug particles get stuck inside the molecules and stay there for a rather long time,  making it easy to find them in a hair sample.


Hair Follicle Drug Test Detection Time

  • How long do the drugs stay in the hair? The hair follicle drug test can detect the drug use about 90 days prior to the test.
  • About 5 to 10 days after the drug is used, the hair grows from the scalp and can be taken for analysis. Other hair on the body can be tested as well but it doesn’t grow as fast as on the scalp so the time period is smudged.
  • If the person lacks head hair, body hair can be obtained to get more or less accurate results as well.


Cut-off Levels

The cut-off levels for various drugs are as follows (in ng/mg):

  • Amphetamines1 AMP/MAMP2 – 500
  • Cocaine – 500
  • Marijuana – 1
  • MDMA – 500
  • Opiates (Morphine/Codeine) – 300
  • PCP – 300


Hair Follicle Test vs. Urine Test

The biggest problem with urine blood testing is the false results. For example, someone ate a poppy seed bagel and the urine tested positive for opiates.  This problem is caused by using the wrong cut-off levels. Another problem with the urine test is that most drugs wear off within 72 hours after using and don’t show up on the test. The detection window of the hair follicle detection test is much wider. Due to rather slow hair growth, the drug particles stay trapped in the hair for up to 90 days.

Meanwhile, a hair follicle sample is much easier to obtain than urine. This is especially useful for parents, who want to check if their children are using drugs. The hair found on the brush or in the bathtub drain can become a useful sample for drug testing.

Best Teenage Guy Haircuts


False Positive Results

Some over the counter meds can cause false positive results. In order to eliminate the possibility of a false positive drug test results, the lab confirms all positive results by GC/MS, GC/MS/MS methods.


At Home Drug Testing Kit

For people, who are not sure that they can pass the employer’s drug test and for the parents worried about their children, there are at home drug testing kits that can produce reliable results. However, the danger of false positive results still exist and the cost of such tests is rather high.

Most Amazing Faux Hawk Haircuts for Men

We hope we answered all your questions about hair follicle drug test detection time and cut-off levels. Passing such tests is often important for career matters. That’s why taking a serious approach is vital to get honest results.

  • Add Your Comment