A hair follicle drug test is one way to screen for recreational drug use orprescription drug abuse.
A section of hair, about 200 strands, is sent to a lab for testing.
Like urine tests, the drugs that can be detected will vary depending on the chosen panel.
SandraMatic/ Getty Images
SandraMatic/ Getty Images
Why Is a Hair Follicle Drug Test Necessary?
Drug tests are used to show drug use or misuse.
These metabolites are found in the hair.
In a laboratory, a procedure called enzyme-linked immunosorbent assay (ELISA) is performed on the hair sample.
The metabolites of a drug react to the test to show a positive, negative, or invalid response.
The test can detect metabolites of drugs, which are substances made from the breakdown of drugs.
It can detect drugs used within the past 90 days.
Home Hair Tests
At-home hair drug tests are available in stores and without a prescription.
They involve collecting hair and then sending it to a lab for analysis.
How to Use a Home Hair Test
Using a home hair test is pretty straightforward.
First, read the instruction manual so you know what to do.
Take the hair sample necessary based on the directions and wrap it in the foil provided.
Then, mail the foil-wrapped hair in the container or envelope with the kit to the laboratory.
Is a Home Hair Follicle Test Accurate?
Because home tests are sent to a lab, they’re comparable to regular hair follicle drug tests.
Neither throw in of test is 100% accurate, even though they go through a two-step process.
Here’s what those terms mean.
Negative
A negative result means no drugs or metabolites were found in the sample.
It doesnt mean the person hasnt used any drugs, however.
The person could have used a drug very recently, before it showed up in the hair.
Or, they might not have used enough of the drug to be detected.
They could also have used other drugs for which the test didn’t screen.
Positive
A positive result means the drug or metabolite was found in the hair sample.
All laboratories have no standard positive cutoff values, which may vary among labs.
Certain foods and medications can cause false positives.
Inconclusive
An inconclusive result may mean the hair sample was contaminated or something went wrong with testing.
You might be asked to provide another sample.
How Accurate Is a Hair Follicle Drug Test?
Drug use takes about seven to 10 days to show up in the hair.
The accuracy statistics of hair follicle testing is also different for different substances.
No, it cannot identify the specific date of drug use.
It can only show whether a substance has been used within the past 90 days.
How Much Does a Hair Follicle Drug Test Cost?
Your health insurance plan may cover the costs, or your employer may if they are ordering it.
If you buy a home test, you pay for all the associated fees.
Other brands can cost less (though might not test for as many substances).
Some urine tests provide instant results, but hair tests must be sent to a lab for completion.
What if I Have No Hair?
This allows persistent drug use to be detected along with more isolated instances of drug use.
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