10 answered questions about hair follicle drug tests

10 things you need to know about hair follicle drug tests

1. How does hair testing work?

Should you have abused drugs in the past, you have to be aware of the fact that, even after a period of abstinence, these can still be found in your hair. Typically you will be tested for a period of 3 to 6 months.

Hair has its own life cycle and, while some hair strands continue to grow and are clean as a result of abstinence, others are dormant (close to the end of their life cycle); this means they stop growing and remain on the scalp for 1 to 4 months more until they fall, which may influence the final results of the analysis.

2. How do drugs get into the hair?

After you ingest a drug, the substance itself or metabolites that are produced as the drug is processed by your body are deposited from your bloodstream into the hair shaft via the hair follicle.

3. How long do drugs stay in your hair?

Once you used drugs, alcohol, or nicotine, these will stay in your hair – at least until the time it is cut. Some of them will degrade a little over time, others like THC traces remain unchanged. The algorithm is quite simple: your hair needs blood in order to grow. So traces of the substances are deposited directly from your bloodstream into the hair. The hair analysis test will show as positive a few days after consumption, as it takes some time for the hair to grow above the scalp.

4. How great a period does a hair analysis cover?

A standard drug hair follicle analysis covers a period of approximately 90 days (3 months).

5. Can body hair be drug tested?

Yes: if, for any reason, a person’s head hair can’t be tested, the second option is body hair from the underarm, chest or back.

6. Hair follicle test, one time use – will it be positive?

While urine tests or saliva tests can pick up one time use, hair tests look for long term usage and are like a timeline of consumption. Moreover, a positive result does not indicate the date of drug use, but rather drug concentration over a certain period of time. In the case of single use, the results depend on various factors like drug type, hair type, metabolism etc. Cocaine consumption on one occasion is more likely to be detectable in hair than a one-off consumption of THC (although this does not come as a certainty). The same applies for alcohol: it depends on the type of alcohol consumed, the amount, and the consumer behavior beforehand etc. For this reason we recommend 100% abstinence for a negative result.

7. Can second hand Marijuana smoke cause a positive result by a hair analysis?

No, second hand marijuana smoke will not generate a positive result for your drug hair analysis if it will be tested for THC-COOH.

8. How can I pass a hair drug test?

The safest way to pass a drug test is not to consume any of the substances that you know you will be tested for. For health reasons, our advice is not to use any illicit substances in general.

9. Is there any way to cheat at a hair follicle test?

Cheating a hair drug test is nearly impossible, considering that the users can’t “clean-up” quickly. If you need the test as an official abstinence proof, the hair sample will be taken by a person certified to do so. The best proven way by far to beat a hair drug test is abstinence. There are different products on the market that promise to clean your hair of the consumed substances. Although this might work, these solutions are not guaranteed to do so. Shaving from head to toe circumvents a hair analysis, but in most cases it would be assumed that a positive result was anticipated and will instead alternative detection methods such as urine testing will be requested.

10. How much does it cost to get a hair follicle drug test?

Depending on the number of substances that you want to test, the prices may vary as follows:

a. Forensis Hair Follicle Test for Cannabinoids



b. Hair Follicle Drug Test (5-Drugs) Forensic

c. Evidence Hair Drug Screening Polytox - 7 drugs



d. Hair Follicle Alcohol Test (EtG) Forensis



Other hair analyses are available for substances like amphetamine, cocaine, opioids, etc. You can find them here.

You will receive the test results in approximately 10 working days.

The results will be interpreted as either positive or negative. In case of a positive result, the concentration of the detected substances will be revealed as well as a short comment on the consumption behavior. Dates or time of the consumption cannot be determined by a hair analysis.



Do you still have an unanswered question about hair follicle analysis? You can also ask us directly here.









