How Long Does THC Stay in Your Hair?

How Long Do Thc Stay In Your Hair

Everything You Need to Know

Hair drug testing is a common method for detecting THC in the body.

As marijuana use continues to gain popularity, drug testing methods have evolved, including hair follicle testing. Unlike other tests, hair follicle testing can detect THC, the psychoactive component of marijuana, for an extended period. So, understanding how long THC stays in your hair is crucial to avoid any negative consequences.

When you consume THC, your body metabolizes it into various compounds, including THC-COOH. These compounds are deposited into your hair follicles through the bloodstream and remain even as your hair grows. Hair follicle testing accurately detects these compounds, making it a reliable method to identify marijuana use.

The detection window for THC in hair is longer than other drug tests. While most drug tests have a window of a few days to a week, hair follicle testing can detect THC for up to 90 days or more, depending on various factors.

How THC is Detected in Hair

Hair detox methods may help remove THC from hair follicles.

THC Metabolites Deposited in Hair Follicles

When you use marijuana, THC metabolites, including THC-COOH, flow through your bloodstream and reach your hair follicles. As your hair grows, these metabolites become deposited in the hair shafts.

Overview of Hair Drug Testing Process

Hair follicle testing involves collecting a hair sample from the scalp, typically from the back of the head, and analyzing it in a laboratory. The sample is washed to remove external contaminants and then broken down to release the metabolites. Chromatography, a process that separates compounds, is used to analyze the metabolites.

The laboratory can detect the presence of THC metabolites in the hair sample and reports the results in picograms per milligram (pg/mg). A positive result is typically considered when the concentration exceeds 1 pg/mg or 5 pg/mg.

It is crucial to understand how THC is detected in hair to be aware of the consequences and make informed decisions regarding marijuana use.

Factors that Affect THC Detection in Hair

Several factors influence the accuracy and reliability of THC detection in hair. Being aware of these factors helps in managing marijuana use and avoiding negative consequences. Here are the significant factors:

Hair Type and Texture

The type and texture of your hair significantly impact THC detection in hair follicle testing. THC metabolites bind to melanin, the pigment responsible for hair color. Therefore, individuals with darker hair are more likely to test positive for THC. Additionally, coarser hair can trap more metabolites, resulting in a longer detection window.

THC Potency and Frequency of Use

The potency of the marijuana you consume and how often you use it affect how long THC remains in your hair. Higher-potency marijuana stays in the hair for longer periods. Frequent marijuana use leads to more metabolites being deposited in the hair follicles, extending the detection window.

Hair Growth Rate

The rate at which your hair grows also affects THC detection. On average, hair grows about 0.5 inches per month, and hair follicle testing can detect THC up to 1.5 inches from the scalp. Faster hair growth results in a shorter detection window.

Use of Hair Treatments or Products

Certain hair treatments or products can affect THC detection in hair. Hair bleach or dye may strip THC metabolites from the hair, potentially producing a negative test result. However, some hair products, such as certain shampoos or conditioners, can cause THC metabolites to accumulate, resulting in a longer detection window.

Understanding these factors empowers individuals to manage their marijuana use effectively and minimize the risk of a positive hair follicle test. However, it is important to note that hair follicle testing is highly accurate, and there is no foolproof way to cheat the test.

How Long THC Stays in Hair

General Timeline for THC Detection in Hair

The duration for detecting THC in hair varies based on multiple factors, including marijuana use amount, frequency, and hair growth rate. Nevertheless, here is a general timeline for THC detection in hair:

  • First-time use: THC may become detectable in hair within seven days.
  • Occasional use: THC can be detected in hair for up to 90 days.
  • Chronic use: THC may be present in hair for six months or longer.

Keep in mind that these timelines are not absolute and can differ based on factors such as hair type, hair color, and test sensitivity.

Factors that Can Extend or Shorten the Detection Window

Several factors affect the duration THC stays in your hair, including:

  • Hair color: THC binds more readily to melanin in dark hair, increasing its detectability.
  • Hair type: Coarse or curly hair can trap THC more effectively than fine or straight hair.
  • THC potency and frequency of use: Higher potency marijuana and frequent use prolong the presence of THC in hair.
  • Hair growth rate: Faster hair growth reduces the accumulation of THC metabolites in the follicles.
  • Use of hair treatments or products: Certain treatments or products can affect THC detection in hair.

Understanding these factors helps in managing marijuana use and reducing the risk of a positive hair follicle test. However, remember that hair follicle testing remains highly accurate, and there is no guaranteed method to cheat the test.

Ways to Remove THC from Hair

If you have detected THC in your hair and want to remove it, consider the following hair detox methods:

1. Clarifying Shampoo

Clarifying shampoos are designed to remove product buildup and impurities from hair. While they may not eliminate all THC, they can significantly reduce the concentration of THC metabolites.

2. Baking Soda and Vinegar

A mixture of baking soda and vinegar can create a detoxifying solution that may help remove THC from hair. However, this method can be harsh on hair and scalp and may cause damage if used excessively.

3. Detox Shampoo

Detox shampoos are specially formulated to remove toxins from hair. They penetrate the hair shaft, breaking down THC metabolites for easier removal. However, the effectiveness varies among different detox shampoos.

4. Hair Razor

Shaving your hair is the most effective method to remove THC metabolites since they are deposited in the hair shaft. However, this method may not be practical for everyone, especially those with longer hair.

When considering these methods, it is crucial to understand their effectiveness and safety. While they may reduce THC concentration in hair, they may not completely eliminate it and can damage hair and scalp if used excessively. Seeking professional advice before attempting any detox method is always recommended.


Understanding how long THC stays in your hair is crucial for anyone using marijuana. Hair follicle testing is an accurate method to detect marijuana use, with a detection window of up to 90 days or more.

Factors such as hair type and texture, THC potency and frequency of use, hair growth rate, and use of hair treatments or products influence THC detection in hair. By understanding these factors, individuals can manage their marijuana use effectively.

If you need information on removing THC from your hair, various hair detox methods are available. However, it is important to note that not all methods are equally effective or safe. Seek professional advice before attempting any hair detox methods.

At Hair Style, we prioritize providing accurate and up-to-date information to help you maintain healthy hair. If you have any questions regarding how long THC stays in your hair or hair detox methods, feel free to reach out to us.

Remember, as marijuana use becomes more prevalent, drug testing methods will become more sophisticated. Stay informed and ahead of the game by understanding how long THC stays in your hair to avoid any negative consequences. Visit Hair Style to learn more.