How Long Does Weed Stay in Hair Follicle?

Weed is now legal in most parts of the world as we recognize more and more medicinal benefits of the cannabis plant. The effects of weed and cannabis products are due to the potent compound called THC (tetrahydrocannabinol).

This psychoactive compound produces the intense ‘high’ associated with smoking weed. The residue of weed and THC metabolites remains in the body long after the effects have worn off. This is why drug testing methods can detect weed even after 90 days of quitting weed.

But how long does weed stay in hair follicle? Can you still fail a drug test even after quitting? It all depends on the frequency of use, potency, and other influencing factors. Let’s discuss the scientific aspects to know more!

How Does Weed Get into Hair Follicles?

The psychoactive compound in weed is called tetrahydrocannabinol or THC. THC is metabolized by the body into its by-products.

These by-products are stored in the body as they bind to the fat molecules. The metabolites also circulate in the body in the bloodstream and reach your hair follicles, getting deposited in the hair shaft.

Our hair grows 1.5 centimeters per month. As our hair grows, the metabolites of THC become a part of the hair strand. Most hair drug tests can detect THC metabolites through this.

As hair tests have the longest detection window for chronic weed consumption, we can conclude that weed stays in the hair follicle from anywhere between 30 days to 90 days post-consumption.

Why Is Hair Follicle Testing Used?

One common method of drug testing for chronic long-term use is through hair samples. Hair follicle tests are very sensitive tests that detect THC metabolites in the hair for up to 90 days after the last use.

This longer period of detection is better than other testing methods, such as saliva and blood tests that only produce a result for seven days post-consumption.

For identifying long-term drug use, hair tests work best. These are usually ideal in legal cases and substance abuse programs where authorities require information regarding the frequent and chronic use of drugs.

How Long Does Weed Stay in Hair Follicle?

Hair tests detect THC for up to 90 days in the case of chronic consumption. For short-term drug use, THC only shows up on hair tests for 20-30 days. The metabolites that become a part of your hair follicles grow out with the strand.

To understand this 90-day window, you need to know more about the average hair growth cycle. As the hair only grows 0.5 inches per month, the standard testing hair length is 1.5 inches. This sets a benchmark of three months of hair growth.

This is why the 90-day window is able to detect the presence of THC metabolites through hair testing. Also, the weed present in the hair does not just fade away. Instead, it stays in your hair strand until the hair naturally sheds or you cut it.

Science Behind Hair Follicle Tests

According to studies, THC metabolites and by-products bind to the melanin in the hair strand. Once they bind, they become a part of your hair and show up on the test for a long period.

Studies also show that hair testing is more reliable than saliva, urine, or blood tests, as these other testing methods have a short detection window.

Factors That Influence Detection Time in Hair Follicles

Certain factors affect THC retention in the body. These factors influence the detection window and test results. What may stand true for one person may not always be the case for you.

If a person who occasionally uses weed or cannabis products takes a test, it may show up for five days post-consumption. On the other hand, if you only take a couple of puffs of weed, it may not show up on tests five days post-consumption.

The detection window varies depending on factors such as frequency of use, potency, hair growth rate, etc. Let’s look into these influencing factors to learn more.

Frequency of Use

Hair testing for THC detection window depends on how much weed you consume and how often. Using certain cannabis products with a high concentration of THC results in more metabolites and by-products.

Our body circulates the THC metabolites in the blood before depositing them in the fat cells and the hair follicles. When cannabis by-products become a part of the hair strand, it’s easier to detect them.

In contrast, people who infrequently use cannabis products have fewer metabolites in the body, and hair test results may come out negative after 30 days post-consumption.

Potency

If hair tests leave you wondering how long does weed stay in hair follicle, you’d be surprised to learn the role of potency. Potency is a critical influencing factor.

A higher concentration of THC results in more THC metabolites in the bloodstream and the hair follicles. Frequently using marijuana results in a longer detection window as more and more metabolites deposit in the hair strand.

What Impacts Hair Follicle Test for Weed?

Hair follicle tests are highly accurate and reliable. They are used in employment settings and for legal requirements. However, some factors might influence the accuracy of these tests.

• Hair Treatments: Hair treatments such as hair dying, bleaching, and perming affect the concentration of THC metabolites in the hair strands. These treatments cannot fully remove the metabolites, but they only affect the concentration required for testing. This may alter the results of weed testing, especially in cases where users smoke infrequently.
• Hair Length: The hair testing practices involve testing the first 1.5 inches of hair near the scalp. As the hair strand grows 0.5 inches every month, this length tests for a 90-day period. Long hair could provide more information regarding the use of weed beyond the 90 days.

Wrapping Up

To conclude how long does weed stay in hair follicle, we can say that a 90-day window is an established time period. Scientifically, these tests measure the use of weed and cannabis products for three months based on a hair testing sample of 1.5 inches in length.

Factors such as frequency of use, potency, and dosage affect the results, but there isn’t a known way to detoxify the hair follicles for a negative test.

Simply washing or cutting your hair does not alter the test results; therefore, hair testing remains the most reliable drug testing method for long-term chronic marijuana use.