How To Pass A Hair Follicle Drug Test. Proven Techniques

Daniel Miller avatar
Daniel Miller, Ph.D, Drug Testing Specialist

Last updated on Mar 1, 2024

Today I’m going to walk you through the steps to pass a hair follicle test. The focus here is on methods grounded in scientific research, and I’ll delve into these studies as well.

These techniques aren’t just effective for THC; they work for meth, opiates, alcohol, and cocaine too.

The tricky part with hair follicle tests, especially for marijuana users, is that THC lingers in your body fat and keeps releasing into your bloodstream over time.

This means your hair could test positive for THC weeks or even months after you’ve stopped using it. That doesn’t seem fair, does it?

So, let’s talk about how to destroy drug metabolites in your hair.

And don’t worry, I’ll cover methods that are safe for your hair, providing step-by-step instructions.

Before diving into the methods, it’s crucial to understand how drugs end up in your hair and how they’re detected in drug tests.

You might be thinking, “Hey Daniel, I’m really not into all the science or specifics about how drug testing on hair works. Can we just get right to the methods?”

Sure: skip to the methods section.

How drugs get into the hair

Hair is mostly made up of a protein called keratin and has three main parts: the cuticle, cortex, and medulla.

Cuticle: This is the outer layer, made up of overlapping scales. Think of it like shingles on a roof. The cuticle guards the inner hair layers and is key to the hair shaft’s strength.

Cortex: The thickest layer, the cortex holds most of the hair’s pigment (color), along with a substantial amount of keratin. It’s responsible for the hair’s elasticity and strength.

Medulla: This innermost layer varies depending on the hair type. It’s a soft, thin core that can be continuous, fragmented, or completely absent.

When you ingest drugs, they enter your bloodstream and get broken down by your body.

These breakdown products, along with the original drug, can then integrate into your hair’s structure.

As hair grows from the follicle, it’s exposed to your body’s internal environment, including the blood.

So, drugs and their metabolites circulating in your blood can get into the hair follicle and become part of the newly formed hair.

This mainly happens in the cortex, where the hair shaft is formed with keratin.

Once drugs are in the hair shaft, they’re essentially “locked in” as the hair continues to grow.

Since hair generally grows at about 1/2 inch per month, the segment of hair showing drug use can be pinpointed.

How does hair follicle drug test work?

To understand passing a hair drug test, it’s crucial to know what the test looks for.

During the test, about 1.5 inches of your hair will be cut and dissolved in a solvent.

The test then measures the concentration of drug metabolites in that solvent. If the level is above a certain threshold, you’ll fail the test.

At the end of this article, I’ll provide a detailed explanation of the hair drug testing process for those interested.

So, the goal is to reduce these drug metabolites in your hair below the cutoff level before the test.

Let’s dive into how you can do that effectively and safely.

Hair follicle drug test cut-off levels

Understanding cut-off levels for hair follicle drug tests is crucial. Here’s a table showing the initial and confirmatory test cut-off levels for various substances:

Substance Detected Initial Test Cutoff Confirmatory Test Cutoff
Amphetamines and Drug Metabolites 0.2 ng/mg Amphetamine: 0.2 ng/mg<br>Methamphetamine: 0.2 ng/mg<br>MDA: 0.2 ng/mg<br>MDMA: 0.2 ng/mg
Cocaine and Drug Metabolites 0.5 ng/mg Cocaine: 0.5 ng/mg<br>Cocaine Metabolites: 0.05 ng/mg
Marijuana Metabolites 0.1 ng/mg THC: 0.05 ng/mg<br>THC-COOH: 0.0002 ng/mg
Opiates and Drug Metabolites 0.2 ng/mg Morphine: 0.2 ng/mg

Codeine: 0.2 ng/mg

6-Acetylmorphine (Heroin Metabolite): 0.2 ng/mg

Methadone: 0.2 ng/mg

EDDP (Methadone Metabolite): 0.05 ng/mg

Buprenorphine: 0.01 ng/mg

Norbuprenorphine: 0.01 ng/mg

How long do drugs stay in hair?

Now, here’s where it gets interesting.

Once drug metabolites enter your hair, they’re there to stay, at least until you cut that section of hair. Drug tests typically examine 1.5 inch of hair, which represents about 3 months of growth.

So, the test can reveal drug use within the last 90 days.

But here’s the catch: drugs stay in your blood for a while before being deposited into your hair.

If you cut your hair about a week after your last drug use, the newly grown hair should be clean of drug metabolites, making it undetectable in tests.

Most drugs linger in the blood for a few days to a week.

However, THC (marijuana) is a different story. It’s fat-soluble, binds to body fat, and is continuously released back into the bloodstream.

This is why marijuana can be detected in urine for a much longer period, especially in heavy users – sometimes months after the last usage.

Consequently, THC can be deposited into newly grown hair for several months after the last use, causing a positive test result.

How to destroy metabolites in hair

The basic structure of a hair shaft consists of three layers: the cuticle, cortex, and medulla. Drug metabolites are stored in the cortex.

To pass the test, you need to remove these metabolites. Here’s a breakdown of the process:

  1. Open Hair Cuticle: This is the first step to accessing the cortex where the metabolites are stored.
  2. Dissolve Drug Metabolites in Hair Cortex: This involves using certain chemicals to break down the metabolites.
  3. Wash Out the Dissolved Residues: After dissolving the metabolites, they need to be thoroughly washed out of the hair.
  4. Close the Hair Cuticle: This is crucial to prevent hair damage and maintain the integrity of the hair shaft.

Various chemicals and special shampoos are used in this process.

Studies have shown that treatments like vodka, disinfectants, bleach, hair relaxers, and others can reduce drug metabolites in hair.

Manipulation of THC Hair Concentrations by Commercially Available Products

In this study, they found that everyday products like vodka, hair tonic, Zydot shampoo, Desderman disinfectant, and Head and Shoulders shampoo could significantly reduce THC levels in hair.

We’re talking about a reduction ranging from 52% with the shampoo to 65% with the disinfectant. his is huge because it shows that these common products can make a big difference in drug test results.

Check out the study here.

Coloring, Bleaching, and Perming: Influence on EtG Content in Hair

Now, this is interesting: coloring didn’t change the EtG (a marker for alcohol) levels much, but bleaching caused a whopping 73.5% decrease.

Perming went even further, with a 95.7% reduction. This tells us that chemical processes can really break down EtG in hair.

The study details are here.

Influence of the Cosmetic Treatment of Hair on Drug Testing

Cosmetic hair treatments like bleaching or dyeing can lower the drug content in hair by 40%-60% for most drugs, and even more for morphine.

The more damaged the hair, the greater the decrease in drug levels. So, it turns out how you treat your hair can really affect drug test results.

Here’s the link to the study: click here.

Influence of Cosmetic Hair Treatments on Cannabinoids in Hair: Bleaching, Perming and Permanent Coloring

This study showed that bleaching and perming can significantly reduce cannabinoid levels in hair.

Bleaching had a stronger chemical degradation effect, while perming seemed to leach out the cannabinoids.

Interestingly, regular hair coloring didn’t have much effect.

Take a look at the study here.

Influence of Chemical Straightening on the Stability of Drugs of Abuse in Hair

Chemical straightening or relaxers can also reduce drug concentrations in hair.

After treatment, only 5-30% of the original drug concentration remained.

This means relaxers can be quite effective in decreasing drug metabolites in hair.

For more details, check out the study here.

Can you pass hair drug test with relaxer?

A quick note: there’s research from 2015 that found hair relaxers can destroy part of the drug metabolites.

So, using a hair relaxer might be a useful step in trying to pass a hair drug test.

You can find this study here. .

Methods to pass a hair follicle drug test

Keep in mind, each method requires multiple applications since studies show that a single application only destroys a fraction of drug metabolites in the hair.

To get these levels below the detectable threshold, you’ll need to apply these methods several times before your test.

DIY remedies

These remedies typically feature ingredients such as bleach and vinegar. They have the advantage of being generally cheaper.

However, there are several downsides.

They can be harsh on both hair and scalp, leading to significant damage, and their application can be painful. These methods usually require multiple applications, which can amplify the damage.

There’s also the risk that the drug test collector might notice the damage to your hair and scalp and choose to take samples from other parts of your body.

Additionally, when you consider the number of ingredients needed, the cost can sometimes rival that of professional detox shampoos.

Lastly, preparing and applying these remedies can be quite time-consuming.

Here’s what some folks have said about DIY methods like the Macujo method:

“Wouldn’t wish that process on my worst enemy.”

“The relaxer really irritates your scalp after the Macujo.”

“Bleach makes scalp burn like hell, apparently, and cause hair/scalp damage.” “Crazy scalp melting treatment.”

“So when I damaged my hair, I felt like my life was ruined.”

“After my test, I decided to cut my hair because I wasn’t trying to look like Patchy the Pirate, so I got a bald fade.”

“I had dandruff and pieces of my scalp were falling out for like a week and a half after.”

Drug test detox shampoos

The advantages of certain hair treatment methods include their ability to not damage hair and some even have effectiveness backed by scientific proof.

On the downside, these methods tend to be more expensive compared to DIY options.

Additionally, it’s worth noting that many shampoos marketed as “detox” may not be effective for drug tests.

Home remedies to pass a hair follicle drug test

The Macujo method

What you’ll need:

Step-by-step instructions:

  1. Protect Yourself: Don gloves and goggles for safety.
  2. Wet Your Hair: Use warm water to dampen your hair.
  3. Apply Vinegar: Massage white vinegar thoroughly into your hair and scalp.
  4. Add Astringent: Apply the Clean and Clear astringent over the vinegar.
  5. Cover and Wait: Put on a shower cap and wait for 30 to 45 minutes.
  6. Rinse: Remove the cap and rinse your hair well.
  7. Shampoo with Aloe Toxin Rid: Lather your hair with the shampoo, then rinse.
  8. Apply Tide Detergent: Lather a small amount of Tide into your hair, then rinse carefully. Be cautious to avoid contact with eyes and mouth.
  9. Repeat if Necessary: Some people repeat the process multiple times before a test.
Warning: The Macujo Method can be harsh, leading to scalp irritation or hair damage.

It’s a tough process, and you should be prepared for potential damage.

Time required:

Success stories of passing a hair follicle drug test with the Macujo method:

Can you use conditioner after macujo method?

Yes, using a conditioner is highly recommended. The Macujo Method can severely damage your hair and scalp, so to mitigate this, use a good conditioner. Here’s how:

This step is crucial to help restore some moisture and health to your hair after the intense chemical treatment. Remember, the goal is to pass the test without ruining your hair in the process.

Jerry G method

Hey there, I’m Daniel, and I’m going to walk you through the Jerry G Method, another popular approach to passing a hair follicle drug test. But hang in there, because this method is pretty intense.

What you’ll need:

Step-by-step instructions:

  1. Safety First: Always wear gloves and goggles.
  2. Dye Your Hair: Apply a permanent hair dye with ammonia. Follow the kit’s instructions carefully, ensuring complete coverage.
  3. Wash Your Hair: Post-dyeing, thoroughly wash your hair with Toxin Rid or another detox shampoo.
  4. Air Dry: Let your hair air dry. Avoid a blow dryer to prevent further damage.
  5. Wait: Give your hair and scalp about 10 days to recover.
  6. Repeat Dye and Wash: After 10 days, redo the dyeing process, followed by a detox shampoo wash.
  7. Baking Soda Paste: The day before your test, apply a baking soda paste to your hair and scalp.
  8. Final Rinse and Shampoo: Rinse out the baking soda, then shampoo once more with the detox product.

Warning: The Jerry G Method is harsh.

It involves chemicals that can cause hair breakage, scalp irritation, and long-term hair damage.

There’s no scientific guarantee it’ll work for a drug test. You should be prepared for noticeable hair and scalp damage.

Time required:

Reverse Macujo method

Now, let’s talk about the Reverse Macujo Method. Strap in and let’s get weird with this one.

What You’ll Need:

  1. Rubber gloves.
  2. Goggles.
  3. Tide detergent (warning: not for body/hair use).
  4. Clean and Clear deep cleaning astringent with salicylic acid.
  5. White or apple cider vinegar.
  6. Hair conditioner.
  7. A shower cap or plastic bag.
  8. A timer or clock.

Step-by-Step Instructions:

  1. Prepare: Suit up with gloves and goggles for protection.
  2. Tide Soak: Wet your hair, then apply Tide generously. Leave it for about an hour.
  3. Astringent Application: Rinse out the Tide, then apply the astringent. Cover with a shower cap for 30 minutes.
  4. Vinegar Soak: After the astringent, soak your hair in vinegar for another 30 minutes.
  5. Condition Your Hair: Thoroughly rinse, then condition your hair. Leave the conditioner on under a shower cap for 10 minutes.
  6. Final Rinse: Rinse out the conditioner and gently towel-dry your hair.

This method, like the Jerry G, is pretty intense.

These treatments are harsh, and there’s no solid scientific evidence they work for drug detoxification. Your hair might become fragile and prone to breakage.

So, before you dive in, remember that these methods can be a huge pain in the butt and potentially damaging.

Always consider the risks and the lack of scientific guarantee in these DIY methods.

Your hair health is important, so think twice before trying these intense treatments.

Best drug test detox shampoos to pass a hair follicle drug test

Old Style Aloe clarifying shampoo by Toxin Rid – the most effective solution for hair drug tests

old style aloe toxin rid shampoo - best shampoo to pass a hair follicle test

Old Style Aloe Clarifying Shampoo by Toxin Rid is currently the most effective shampoo for passing a hair follicle drug test.

It’s guaranteed to work, making it the best option for moderate and chronic weed users.

This deep-cleaning formula is gentle on the hair, removing toxins like THC without causing damage.

Unlike some other products that can cause scalp irritation, Old Style Aloe Clarifying Shampoo is gentle and soothing.

It contains aloe vera to prevent drying, as well as a wealth of other natural conditioners to keep your scalp hydrated, healthy, and happy.

Originally designed to remove hair contaminants, this shampoo has become known for its ability to eliminate drug toxins.

It comes in a 5-ounce bottle, providing multiple washes.

Best of all, it’s legal and has numerous positive customer reviews and success stories.

For the best results, it’s highly recommended that you use the Ultra Clean along with the Old Style Aloe Toxin Rid.

Priced at $199, this shampoo may seem expensive, but it’s the only product we can truly recommend for guaranteed results.

It can be used in Jerry G or Macujo detox methods.

How to use

To use, start 3-10 days in advance of your test. If you have less time, take multiple showers daily.

During each washing, lather the shampoo in your hair for 10 to 15 minutes.

Ensure you use the shampoo 15 times before your test for optimal results.

We suggest the following washing routine:

Focus on the scalp, where toxins are found. This shampoo offers a reliable and effective solution for passing hair drug tests.

Zydot Ultra Clean – best for light users

Zydot Ultra Clean Shampoo is a more affordable option for those looking to pass a hair drug test.

However, it’s important to note that it may not be very effective for regular marijuana users. This product is best suited for light weed users.

This shampoo is gentle on both hair and scalp, ensuring that it won’t damage your hair or cause scalp irritation. It is a 3-step solution that includes:

One of the downsides to Zydot Ultra Clean Shampoo is that it can be somewhat complicated to use and may take up to 45 minutes to complete the process.

However, it is priced at just $35.99, making it a more budget-friendly option.

It works best when combined with other products.

How to use

Zydot Ultra Clean Shampoo should be used on the day of the test, and its effects last for about 5 hours.

To use the product, follow these steps:

While Zydot Ultra Clean Shampoo might not be the most powerful solution, it’s an affordable option for those with lighter drug usage.

How to pass a hair follicle test with dreads

Dreadlocks pose a unique challenge for hair drug tests. The tight weaving makes it hard for detox products to penetrate and cleanse thoroughly.

Tips for dreadlocks:


If you’re okay with the risk of damaging your hair and scalp, DIY home remedies might be an option.

However, I highly recommend the combination of Toxin Rid Aloe Shampoo and Zydot Ultra Clean, which has been scientifically proven to be effective.

When considering these methods, always weigh the consequences of failing a drug test against the risks of hair and scalp damage.

Make a well-informed decision that best suits your situation. Remember, you do you, boo!

Weighing your options for passing a hair drug test

In conclusion, you can take a risk and try the Jerry G method or any other home remedy to pass a hair drug test. However, it’s crucial to be mindful of the potential side effects.

Applying harsh substances like bleach, vinegar, and other chemicals to your hair may cause significant damage to both your hair and scalp.

If you’re not keen on experiencing your scalp falling out for a week and a half and would prefer a proven solution, consider using a product like Old Style Aloe Toxin Rid Shampoo. Make an informed decision that best suits your needs and takes into account the possible consequences of each approach.

How to read hair drug test results

It’s essential to understand how to read the results of a hair follicle drug test, as this can provide valuable insights into your drug usage history and any necessary steps to take.

A negative result can be determined within 24 hours of hair removal.

A negative result indicates that you haven’t engaged in illicit drug use over the past 90 days.

On the other hand, a positive drug test is confirmed after 72 hours.

All non-negative tests undergo a second gas chromatography/mass spectrometry (GC/MS) analysis. This test confirms a positive result and identifies the specific drugs used.

In some cases, improper collection of the hair specimen may result in the test being rejected completely. In this case, the test may need to be repeated.

The laboratory responsible for testing will deliver the results to the individual or organization requesting the test. They’ll use confidential means, such as secure fax, phone calls, or an online interface, to share test results.

Keep in mind that lab results are considered confidential health information. You’ll need to sign a release before the results are passed on to your workplace, ensuring your privacy is protected.

Who needs to pass hair drug tests


Professional and college athletes may need to pass hair follicle drug tests to comply with their sport’s regulations and avoid potential sanctions.

These tests help maintain a level playing field and ensure athletes’ health and safety.

Military personnel

Military members may undergo random or pre-deployment drug testing to adhere to substance abuse and performance-enhancing drug regulations.

These tests help maintain military readiness and protect servicemembers.

How to Successfully Pass a Military Drug Test in 2024: Proven Strategies

Pre-Employment Screening

Employees working with hazardous materials or heavy machinery, such as truck drivers, miners, and oil rig workers, may need hair follicle drug tests to ensure workplace safety and minimize risks associated with impaired judgment from substance abuse.

Parole and probation monitoring

Individuals on parole or probation may receive periodic hair follicle tests as part of their supervision requirements. These tests ensure abstinence from illicit substances during monitoring and rehabilitation.

How to Legally Pass a Drug Test While on Probation

Protecting vulnerable patients

Employees in industries requiring physical contact with customers, such as nursing homes, may undergo routine hair follicle testing. This provides extra security for vulnerable individuals in their care, protecting them from potential harm caused by impaired employees.

Recovering from addiction

People in therapeutic programs for overcoming addictions, like AA or NA, may have periodic hair follicle tests as part of their sobriety requirements.

These tests help track progress toward recovery goals and mitigate risks from continued substance abuse.

Child custody considerations

Parents involved in custody battles may be subject to hair follicle tests to assess substance use before or after filing for divorce. These tests inform courts’ decisions on child custody rulings.

Medical treatment monitoring

Lastly, individuals undergoing treatment for medical conditions, like cancer, may need a one-time hair follicle test so doctors can determine

if recent substance use could interfere with prescribed treatments. Additionally, a urine drug test might be required to check drug remnants in the system.

Which companies conduct hair follicle drug testing in the USA?

Trucking and transporting

In the future, all truck drivers may be required to pass a hair drug test.

However, many trucking companies already mandate this. Some of these companies include AAA Cooper, USA Truck, Crete Carrier, Roehl Transport Inc., Knight Transportation, TransAm Trucking, ABF Freight System, Western Express, Acme Truck Line, and Rush Trucking.


Construction is a high-risk industry where a lapse in judgment, especially when operating heavy machinery, can result in serious injuries or losses. To minimize workplace accidents, contractors may opt for drug screens, including hair drug tests, as they are deemed most effective.

Financial industry 

Financial decisions can make or break a company, and employers in this industry often test for drug use to minimize the risk of missteps. Ensuring sobriety can be crucial in maintaining a company’s financial stability.

Federal workers and regulations

Despite the legalization of marijuana for medical purposes in more than 50% of US states and the steady increase in states legalizing non-medical adult use, marijuana remains illegal at the federal level. As a federal worker, adherence to federal rules is crucial, which may include passing a hair follicle drug test.

Manufacturing and shipping warehouses

Working in a manufacturing plant or shipping warehouse requires sharpness and attentiveness, especially when operating heavy machinery like forklifts. Employers may test for substance use to ensure employee safety and maintain low insurance costs.

The information on this website about detox products and synthetic urines is for educational purposes only. We do not endorse or condone their illegal use. Always consider the laws in your area and the potential legal consequences. Consult with a healthcare professional before using any products. Your responsibility and well-being are paramount.