Lawyers, employers as well as medical professionals, are showing an increased interest in hair drug screening because they can learn and know if the person has been using illegal or legal drugs or misusing any prescription medicines.

In this article, we will talk about how hair screening work, how to use Do-It-Yourself and home kits, as well as what the test results mean. We will also discuss the cost as well as the accuracy of these screenings, whether individuals with little to no hair can still provide a viable sample and how follicle screenings compared with other conventional drug screening methods like urine or blood-based screening. We will not discuss how to pass a hair drug test since the article will tackle the process involved in hair drug screening

What is a hair drug test?

Hair follicle drug screening is a test performed to detect any components or toxins metabolite from narcotics like marijuana or cocaine. The screenings can determine any pattern of illegal or legal substance, misuse of prescription medicines and even alcohol, use of a certain period, usually three to four months or 90 to 120 days for test samples that are collected from the person’s head.

Testing laboratories or clinics can use any hair from body parts like the head, neck, arms, legs, chest, and in rare cases, hair from the private parts of the test subject. It can detect certain forms of narcotics like amphetamines (MDMA or ecstasy, MDEA or eve and methamphetamine), cocaine, marijuana, opiates (codeine, heroin or morphine) and PCP or angel dust.

Why is the test important?

An individual may need to subject themselves to substance screening for legal, medical or employment purposes. Some companies require their employees or even applicants to undergo drug screenings as a part of their company protocol and their application process, especially for jobs that have a high risk of getting injured.

Employers can also subject their employees to random substance screening, or they can request following serious incidents or accidents. In the United States, drug use and drug testing laws differ from every state. There are states the prohibit companies from subjecting their employees from any forms of drug screening on a random basis.

In these places, employers need to provide evidence that can support their decision to submit a particular employee to a specific illegal or legal substance screenings. The court can require testing for any individual that is on probation or during adoption, domestic violence or child custody cases.

Hospitals, clinics or health care providers can also request a substance screening for individuals that are at risk of alcohol or substance abuse. But it is very important to know that the testing needs written consent from the person who will be subjected to it.

What happens during these tests?

A hair drug screenings can take place in screening laboratories, clinics, workplace, or even at home. During the process, the testers will remove a small sample of hair from the person’s head or other body parts like the arms, legs, armpits, neck or private area and send it to an accredited laboratory or clinic for overnight screenings.

Prescription medicines and certain foods like poppy seeds can contain components that can lead to false positive results. Hair samples will undergo a two-step process to make sure that the result of the test is accurate.

The first step involves ELISA or enzyme-linked immunosorbent assay test: a rapid screening method

If the enzyme-linked immunosorbent assay test produces a positive result for a specific substance, the laboratory technician will need to do a retest of the test sample using a confirmatory chromatographic screening test lie GC-MS or gas chromatography-mass spectrometry to rule out a false positive result.

To know more about ELISA screening, you can visit 

Using a home kit

People who want to undergo the test can order an at-home hair testing kit on the internet from authorized providers. The packages will include instruction manuals and pre-paid envelope to be used for mailing the test sample to the laboratory or clinic. To use these at-home kits, first, you need to read the instruction manual that comes with it carefully. Then, collect an ample amount of test sample according to the kit’s directions.

Wrap the test sample in a piece of aluminum foil. Place the sample that is wrapped in foil in the envelope provided by the kit. And lastly, mail the envelope with the sample inside to the testing laboratory or clinic for an overnight analysis. The individual can access their test results by contacting the laboratory or clinic via their toll-free number or checking their website and using the identification number provided by the testing kit.

What does the result mean?

The result of the drug screenings can be positive, negative or inconclusive.


A negative test result will mean that the clinic or the laboratory did not find any presence of drug substance or metabolites in the sample. It also means that after testing positive in ELISA screening, they are unable to confirm the result using GC-MS.


The sample that produces positive results for ELISA testing will undergo a confirmatory screenings like GC-MS. A positive result in both ELISA and GC-MS means that the clinic or laboratory confirmed the presence of drug metabolites in the test sample.


If the sample is either contaminated or compromised (something goes wrong during the delivery or the testing), the lab will declare the result as inconclusive. In cases like this, the person needs to provide another set of a sample to the clinic or laboratory.

How accurate are these screenings?

Hair drug screening can determine whether an individual is using legal or illegal substances within the past 90 days. But, the screenings can’t pinpoint the exact time or date of drug use because the hair growth rate can vary with every person. Although the samples undergo a strict two-step process, they are not 100% accurate.