Hair Drug Testing Popular Questions & Answers


What is a hair follicle drug test?

Since hair growth is fed by the bloodstream, the ingestion of drugs of abuse is revealed by analyzing a small sample of hair. Our testing method measures the drug molecules embedded inside the hair shaft, eliminating external contamination as a source of a positive test result. Hair drug testing results cannot be altered with shampoos or other external chemicals.

How accurate is hair testing for drug use?

Hair testing is the most accurate and effective method of detecting drug abuse. Using a small sample of hair cut at the scalp, a hair follicle drug test evaluates the amount of drug metabolites embedded inside the hair shaft.

The testing technology is designed to show the presence of drug levels which would only be consistent with the ingestion of drugs. All samples are tested using a radioimmunoassay screen. Before any positive drug test result is reported, the sample is subjected to a second, confirmatory test using gas chromatography mass spectrometry (GC/MS), considered the gold standard for forensic drug testing.

What drugs does HairConfirm™ screen for?

Our HairConfirm™ hair drug screening test detects five different drug classes: Cocaine (cocaine & benzoylecgonine), Marijuana, Opiates (Codeine, Morphine & 6-monacteyl morphine), Amphetamine (Meth/amphetamine & Ecstasy) and Phencyclidine (PCP,  angel dust).

The fact that our HairConfirm drug test screens for the five most popular drug classes is a major advantage to parents. Many parents use this test to detect possible marijuana use but some do not believe that marijuana is ‘that’ harmful. However parents should be aware that teens who start out as casual marijuana users are more likely to use harder drugs such as ecstasy, meth and cocaine than teens who do not. So it is important to test your child at the first signs of suspicious behavior that could be the result of drug use and even if there are no signs. Our HairConfirm hair drug test kit is a very effective drug-prevention tool and will help in aiding parents to enforce a drug-free policy in their home.

In some cases, when the donor has used marijuana, a hair drug test, including HairConfirm, may be unable to detect the THC metabolite due to the fact that the metabolite was unable to bind with the hair shaft. This can be caused by the type/quality of the marijuana smoked/ingested, or by what it has been mixed with, e.g. tobacco. As a result, the result for marijuana may be negative.

What time period does the HairConfirm™ hair drug test cover?

HairConfirm™ will detect drugs for a period of 90 days. The test requires a hair sample of 1.5 inches in length. Each 0.5 inch represents 30 days. The hair sample must be cut as close to the scalp as possible and the most recent 1.5 inches are tested.

How does hair drug testing compare to urine drug testing?

When compared to the more traditional forms of testing, i.e. urine drug testing, hair samples can detect a longer period of drug use. With urine, most drugs are undetectable if urinalysis is done more than 2-3 days after use, with the exception of marijuana, which may be detected for a slightly longer period of time. After the 2-3 day period, a urine donor will often test negative for drugs and slip through the urine screening process. With hair samples, the only time limitation for detecting drug usage is imposed by the length of the donor’s hair. Each ½ inch of head hair provides an approximately 30-day history of drug use. The standard for the industry is to test 1.5 inches, which provides a 90-day history of the donor’s drug use.

How effective is a home hair drug test kit for detecting drug use?

In side-by-side comparison studies with urine drug screens, hair follicle drug testing has uncovered significantly more drug use. In two independent studies, hair drug testing uncovered 4 to 8 times as many drug users as urinalysis for evidence of drug use.

Can hair be affected by cross-reacting substances such as over-the-counter medications?

Enzyme-immunoassay antibodies (EIA), similar to those used to test urine, are used for the initial drug screening in hair; therefore the potential for substances such as over-the-counter medications to cause a false positive screening result does exist. To eliminate the possibility of reporting a false-positive result due to cross-reactivity, our laboratory performs Gas Chromatography Mass Spectrometry (GC/MS) for all specimens that screen positive.

What does a hair follicle drug test cost?

Our HairConfirm tests typically cost approximately $65-$85 depending on the panels tested.


How fast does head hair grow?

Studies indicate that head hair grows on average of 0.5 inches (1.3cm) per month. This growth rate varies slightly (estimated at ± 0.2 cm per month), consequently there is some (± 1 week) time variation possible. Head and body hair do not grow at the same rate; body hair grows at a slower rate.

How soon after use can a drug be detected in hair?

It takes approximately 4-5 days from the time of drug use for the affected hair to grow above the scalp. Body hair growth rates are generally slower and cannot be utilized to determine a time frame of drug use.

Can tests be run on people with little or no hair?

Hair can be collected from several head locations and combined to obtain the required amount of hair. If the head hair is too short, body hair can be used as a substitute. If body hair is used the time frame represented by the test is approximately one year due to the different growth pattern in hair below the neck. NOTE: DO NOT mix head and body hair.

What is the shortest detection time period that can be accurately evaluated?

The minimum drug detection period is approximately one month (0.5 inch).

Can hair collected from a hairbrush be used?

No, we do not recommend taking a hair sample from a brush or any other source (e.g. pillow, clothing) as the sample may be contaminated and there is no guarantee that the hair is from your child. The laboratory will reject a hair sample if it is not collected and prepared as per the instructions.

How does the hair drug test work?

Using the detailed instructions as a guide, collect a hair sample of approximately 90-120 hairs. Mail the hair sample to our laboratory, using the pre-addressed envelope provided. The laboratory will analyze the hair sample for evidence of drug use. Using your HairConfirm™ Specimen ID number, passcode and email address, you must register your test once you have mailed the samples to the laboratory. Go to the results section to obtain the secure results.

How do I collect the hair sample?

To see our hair collection instructions please click here.

How do I ship the sample to the lab?

  • Once you collect the hair, place them in the collection foil as directed in the instructions.
  • Place the Collection Foil in the Hair Specimen Pouch provided in the kit. Seal the pouch with the small security label provided on the specimen ID card in the kit. Put initials and the date on the small security label. (Place the rest of the Specimen ID card in a safe place, as you will need this ID number and passcode to register your test and obtain your results).
  • Place sealed Hair Specimen Pouch into clear specimen bag provided and seal the bag
  • Place sealed bag in into prepaid, pre-addressed envelope.

How long will it take to receive the drug test results?

We know it is important that you receive results as quickly as possible. HairConfirm™ has the fastest turnaround time for hair testing.

Using the shipping label included in this kit, the laboratory will receive the sample the next business day. Tests results are available 2-3 business days after the sample has been received by the laboratory.

Lab Procedures

Is your laboratory CLIA accredited?

Our lab is accredited by the Clinical Laboratory Improvement Amendments (CLIA) and all tests are supervised, reviewed and approved by Ph.D. staff scientists. We have performed over 1.5 million hair tests to date.

What are the drug test cut off levels used by HairConfirm?

    • HairConfirm Hair Follicle Drug Test follows the cut-off levels generally accepted industry-wide. These levels are based in part by minimum detection levels for gas chromatography mass spectrometry GC/MS confirmation. The cut-off level for each drug varies (depending on the type of drug) and is listed below.

Although HairConfirm Drug Tests are designed to detect a very small amount of a drug in the hair, if the amount is below the established cut-off level, you may test negative for that drug even though you may have taken the drug.

Drug Class Screening Cut off level Confirmation Cut off level
Amphetamine, Methamphetamine (Ecstasy)
500 pg/mg hair 500 pg/mg hair
Cocaine & Benzoylecgonine
500 pg/mg hair 500 pg/mg hair
Codeine, Morphine & 6-MAM (Heroin Metabolite)
200 pg/mg hair 200 pg/mg hair
PCP, Hallucinogen (Angel Dust)
300 pg/mg hair 300 pg/mg hair
Carboxy- THC
1 pg/mg hair>/td> 0.10 pg/mg hair
Pg/mg= picogram per milligram of hair

Does the lab provide Gas Chromatography Mass Spectrometry (GC/MS) confirmation for all positive results?

Yes GC/MS confirmation is performed on all positive results to avoid any false positives.


How will I obtain the test results?

After you have mailed the hair sample, you must register your test here to obtain your results. You will need your Specimen ID number, passcode and email address to register.

The results will be available approximately 2-3 business days after the hair sample is received by the laboratory. Please note that lab processing times may vary.

How will I read the test results?

The results will indicate a positive or negative result for each drug class. In addition, when a donor tests positive, the result will provide an assessment of hair dose response to identify whether the donor is a low (occasional), medium (weekend, daily) or high (constant) user (not including Marijuana).

Watch our video below on how to read the results of our HairConfirm Hair Follicle Drug Test kits.


What does the test report look like?

Click here to download a sample results report.

Will the test result remain confidential?

Yes, the test results are kept completely confidential and are for your use only. No names or social security numbers are used in the testing process. The only identification is the specimen ID number provided with the kit.

Does external exposure to certain drugs, like Marijuana or crack smoke, affect the hair test results?

To rule out the possibility of external contamination, HairConfirm™ hair drug testing (where appropriate) looks for both parent & metabolite (bi-product) of drug usage. For Marijuana analysis, our laboratory detects only the metabolite (THC-COOH). This metabolite is only produced by the body and cannot be an environmental contaminant.

Does hair color affect results?

Hair color is determined by the amount of melanin in the hair. It has been shown experimentally, through actual hair samples, as well as determined in court, that hair color has NO basis in fact.

Why did Marijuana (THC) show up negative?

In some cases, when the donor has used marijuana, a hair test for THC, including HairConfirm, may be unable to detect the THC metabolite due to the fact that the metabolite was unable to bind with the hair shaft. This can be caused by the type/quality of the marijuana smoked/ingested, or by what it has been mixed with, e.g. tobacco. As a result, the result for marijuana may be negative. This is only the case with THC and not with the other illicit drugs (Cocaine, Heroin, etc). In most cases with adults it takes smoking 5-6 full joints in order for enough of the drug to “stick” to the hair to show a positive – this is an average number. If the amount consumed by the individual was less than that it might not show up in a drug test.

In the case where a long term THC use is present (like medical marijuana) sometimes the individual’s body can create a masking agent that would hinder the marijuana in a drug test.

Statistics have shown that teenagers who have used marijuana are more likely to use other potentially more dangerous drugs, than those who have never used marijuana. So if you suspect the individual may be using marijuana it is important to remember that you are also testing for those illicit drugs.

Do you have any support services after the results?

Below is a number that you can contact in case you’d like to talk to a counselor:

The Boys Town National Hotline 1-800-448-3000

The Boys Town National Hotline is a 24-hour crisis, resource and referral line especially for kids and parents. Trained counselors can respond to your questions every day of the week, 365 days a year. The National Hotline can help teens and parents with suicide prevention, depression, school issues, parenting troubles, runaways, relationship problems, physical abuse, sexual abuse, emotional abuse, chemical dependency, anger and much more.