5 ways to avoid a hair test: And why they won't work

John Wicks

John Wicks

on Jan 16, 2020

Shaving your head to avoid a hair test for drugs may seem extreme, but people do it. Spending a fortune on pills and potions that promise to eliminate all traces of drugs? People do that, too.

A quick Google search will reveal all sorts of articles telling you how you can cheat a hair drug test - as well as (somewhat dubious) tales of how some have succeeded.

But which of these cheats work - and which don’t? We’ve put together a guide to five common methods people use to cheat the system - and how successful they really are.

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1. Wearing a wig to cheat a hair test

Let’s face it, most of the time it’s easy to spot a wig a mile off. They’ll often fit badly, fail to match the wearer’s colouring or facial hair, and if they’re not well secured, they have a tendency to slip. The majority are also made from synthetic hair, rather than real human hair - so even if they fool us, there’s no chance they’ll fool our mass spectrometers, which read the entire chemical composition of the sample.

But not all wigs are created equal. If someone’s really dedicated to avoiding a test, they could spend hundreds of pounds on a bespoke, professional wig, made of human hair. They’re much harder to spot by eye, and our testing equipment will detect them for what they are - perfectly real human hair.

That’s where our strict collection procedures come into play. Our chain of custody demands that someone who knows the person being tested - a lawyer or social worker for instance - be present when the sample is collected. If a person turns up with a wildly different haircut to a couple of days before, they will notice and ask some tough questions.

2. Shaving your hair off to avoid a hair test

While it’s true we can’t collect hair from a bald head, a freshly shaved head on the day of a drug test with hair is more than a little suspect. What many people who do this don’t realise is that in the absence of head hair, we’ll simply test body hair instead. And because body hair grows at a slower rate than head hair, it can show a longer period of drug use. They’ve actually made their situation worse.

Those who do realise sometimes take things one step further, and remove all traces of follicular growth from their body. Not only is this painful and time-consuming, it sets off our suspicion radar even more. Even then, all is not lost. In situations like these, blood and urine tests can still give an indication of recent drug use, as can fingernail testing - and there’s nothing to stop us from calling a subject in for a retest when hair has grown back.

3. Bleaching hair to trick a hair test

It’s true that bleaching hair can remove toxins. Just one bleach can remove between 40% and 80% of the metabolites in a single sample by damaging the hair shaft. However, that still means that 20% to 60% of the metabolites are still there to be detected - and in using LC-MS/MS to test a hair sample, they will be found.

If hair is bleached regularly, it may be that no trace of drugs can be found - even if they have been used within the testing time frame

If hair is bleached regularly, it may be that no trace of drugs can be found - even if they have been used within the testing time frame. Here, again, we can easily use body hair as a fallback - and blood or urine tests if a subject turns up with a suspiciously blond head of hair and a fuzz-free body

4. Swapping hair samples to avoid drug use being detected

We’ve heard tales of subjects attempting to steal samples once we’ve taken them, and swap them with those taken from drug-free friends. Some even wilder plans have been attempted - like identical twins trying to fool the system by switching places on the day of the test. In all honesty, that won’t wash with us.

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It goes back to the chain of custody again. While the cutting of hair is a simple process, we adhere to an incredibly stringent process when collecting, packaging and testing in our labs. In short, try swapping samples, and you’re guaranteed to fail. Everything we do is subject to strict controls that ensure that our results will stand up in court

5. Internet-bought pills or shampoos to remove drugs from hair

There are products on the market that can penetrate inside the hair shaft and remove any traces of toxins. Sounds too good to be true, doesn’t it? That’s because it is.

There’s no proof that these “detox shampoos” and other products have any effect whatsoever. Their sellers prey on the fears and anxieties of those waiting for hair testing for alcohol or drugs - and their ridiculously high prices reflect this. Those who are suckered into buying will find themselves spending a lot of money on a test result that will be no different.

A Wiley research paper from late 2017 highlights positive user reviews of certain shampoos online - but also notes that some of those who passed after using such a product may simply have not used enough of the substance to be detected at its defined cut-off. Meanwhile, a further research paper reveals that a single treatment with one specific shampoo was not enough to reduce drug concentrations to below the cut-off.  


The Internet is awash with stories of how individuals have successfully cheated a hair drug test. While most are likely fantasy, some may well be true - which just serves to demonstrate how vital it is to use a professional, fully accredited testing laboratory.

The chain of custody processes that the laboratory has in place should ensure that any attempts to cheat the sample collection itself are foiled. The expert interpretation of the results by the lab will take into consideration any change recognised in the hair’s appearance before the sample is taken. The testing method itself also has a huge part to play. LC-MS/MS testing is incredibly accurate and sensitive, precise and thorough: even if it’s not visually obvious that a donor has treated their hair or is wearing a wig, the test will pick it up.

Try fooling us if you like - but the only way to guarantee a clean hair test is to avoid drugs altogether.


John Wicks

John Wicks

John Wicks is one of the UK's leading experts in drug testing and has been for over 25 years. He is CEO and co-founder of Cansford Laboratories, a drug and alcohol testing laboratory based in South Wales. John is one of the ‘original expert minds’ who alongside co-founder Dr Lolita Tsanaclis, is responsible for bringing hair testing to the UK.

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