How Do Hair Follicle Drug Tests Work?

Employers, court systems, medical organizations, and some schools use drug testing to check for traces of substances in a person’s system. While urinalysis drug screenings are the most popular type of drug test, another one that is increasing in popularity is hair follicle drug tests. If someone is a drug user, the last thing they want is to have to submit to a hair follicle test. This is because hair follicles can contain traces of drugs and alcohol for several months – even after a person stops taking a substance. Let’s take a deeper look into why these drug tests are used and how hair follicle drug tests work.
Why Are Hair Follicle Tests Necessary?
People may need to submit to a drug test for legal, medical, or employment purposes. Many companies and employers ask prospective job candidates to take a drug test when they apply, especially if it is a job with a high risk of injury or liability. People who are arrested for drug-related offenses or for public intoxication may also be asked to submit a drug test. Similarly, courts may require drug testing for individuals on probation, in custody battles, during domestic violence cases, and more. Lastly, drug tests are also used in the healthcare field if a physician suspects drug or alcohol misuse.
Hair drug tests in particular are used to detect substances for up to 3 months after a person has used drugs. While urine drug tests tend to be cheaper, faster, and more accessible, hair follicle tests have proven to be more useful for monitoring substance misuse in high-risk individuals due to the longer detection period.[1]
What is the Process of Getting a Hair Drug Test Like?
A person may show up for their test in either a lab or hospital setting unless they have an at-home kit which can either be tested at home or sent to a laboratory. It doesn’t matter whether they’ve dyed, styled, or washed their hair – these things won’t affect the accuracy of the test results.
The way these tests work is that a collector or healthcare professional will cut around 100-120 hairs from the base of the head. They will take hair from different places so that the missing hair is not noticeable. If the person does not have hair on their head, body hair will work just as well. The hair collected cannot come from a hairbrush or the like – it must be taken directly from the body.
After the hair has been collected, it will be placed in foil and secured in an envelope until it is sent off for testing. The process is not invasive and will only last for a couple of minutes. Then, people can return home and wait until the results come back from the lab.
How Does A Hair Follicle Drug Test Work?
Once a hair sample has been collected and sent off to the lab, the hair will be tested. The first test run on the hair sample is referred to as the ELISA test. ELISA determines if a hair sample is negative, or, in other words, if there are no traces of drugs in the hair sample. This test only takes 24 hours, so people who have a negative test should get their results the next day.
If ELISA does not confirm a negative result, further testing is needed to confirm a positive hair follicle drug test. Nonnegative hair drug tests will have to go through an additional screening process called gas chromatography/mass spectrometry (GS/MS). GS/MS will confirm a positive test result within 72 hours. It will also indicate the specific type of drug used by the individual.
In very rare cases, hair follicle drug tests will come back inconclusive. If the sample is rejected, the test may be repeated with a new hair sample. Since the lab results are confidential health information, individuals will be notified by a secure and private means such as by phone or fax.
When a person takes drugs, the organs metabolize the substances as they enter the bloodstream. As these metabolites flow throughout the body, they are deposited and excreted through urine, sweat, and even hair. As a person’s hair grows, trace amounts of chemicals and metabolites that have been deposited in the hair will remain. This is why chemists can use strands of hair to test for substance use.[2]
How Accurate Are Hair Follicle Drug Tests?
Most substances can be easily detected in hair drug tests for up to 90 days after the last time a person used a substance. That being said, drug tests are unable to identify exactly which day a person used a substance. Since hair tests undergo a two-step testing process, they provide fairly accurate results with false positives being extremely uncommon.
There are a few factors that can affect whether or not a substance is detected on a hair drug test. These include:
- The amount of melanin in a person’s hair – some drugs bind to hair with melanin easier than lighter hair colors.
- How much the person sweats – sweating can help expel drugs from the system at a faster rate.
- The number of drugs a person has taken – people who abuse drugs in larger amounts and for longer amounts of time are more likely to fail a drug test.
Hair follicle drug tests can detect many different types of substances, including:[3]
- Opioids
- Marijuana
- Methamphetamines
- Amphetamines
- PCP
- Ecstasy
- Cocaine
How to Pass a Hair Drug Test
In the end, the only way to ensure a person passes their drug test is to not use drugs for 90 days before your test. Unlike urine samples, there is no easy way to cheat a hair drug test – especially since the sample is collected by a professional directly from the body. Of course, there are many products on the market that claim they will make hair drug tests come back negative, however, these usually don’t work.
If you know you have a drug test coming up and are unable to stop using drugs, you might have a substance abuse problem. Being unable to stop using, even when you want to or need to, is a sign of drug addiction. Don’t worry – addiction is completely treatable. Pick up the phone and call now to see how we can help you get started on your recovery.
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