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Smoking pot is an excellent way for you to brush off some of the stress and challenges you’ve been facing lately. Many people around the world use pot for various purposes, both medical and recreational.

However, one of the main issues that arise fairly often is the fact that almost every employer will require testing at some point. There are quite a lot of methods for cheating these tests available online, but most of them are either completely useless or aren’t worth going through.

The main question most people have is – how long does THC stay in my hair? To answer that question, we’ll take a small journey and see how does it get in your hair and how most of these tests work. Once we break it down a bit, the answer will become more apparent.

How THC Gets Into Your Scalp?

How Long Does Marijuana Stay In Your Hair? 1Once cannabinoids enter your bloodstream, they travel to the receptors on your body cells and bind to them. However, during that travel, some of the metabolites come into the blood vessels responsible for feeding your scalp cells.

In those cells, there is a gap between the vessels and hair papilla, which is where THC jumps the gap and enters the space where hair growth occurs. As one can imagine, the hair from the root grows upwards, thus carrying THC along for the ride past the scalp.

While the incubation process seems complicated, it actually can be brought down to a simple sentence. Once you smoke, vape, or ingest cannabis, it travels through your bloodstream and cannabinoids latch to different cells. One of those is the hair papilla which then becomes “infected” and a carrier of cannabinoids1.

How Much Time Does It Last There?

There is a lot of talk going on about this question in particular, and only a few people seem to have somewhat accurate data. When it comes down to answers, there are two potential ones.

The first one is for people who are facing a test, and the second one is for individuals who would like to know the answer just out of curiosity.

As for the first group of people, the safest timeline you should consider is three months. However, it’s not because weed stays in your hair for three months, but because tests go that far back. They usually use 1.5 inches of your hair for testing, which is approximately equal to three months of growth given the fact that hair grows at a rate of about half an inch per month2.

If we exclude testing, it’s safe to say that weed stays in your hair more or less indefinitely. That’s why most people resort to cutting their hair before the test and abstain so that new (clean) hair can grow out.

The question most people frequently ask is whether one hit of herb will make any difference. The answer is – it probably won’t, but if you’re aiming to apply for a lucrative job, it’s probably not worth risking in the first place.

How Does Hair Testing Detect THC Compounds?

How Long Does Marijuana Stay In Your Hair? 2The hair first gets washed to remove any potential contaminants once it’s collected. Subsequently, it gets digested in a solution that is meant to break it down further into its essential components – mainly keratin.

After that, it goes through a laboratory procedure that uses antibodies to bind the chosen molecule. The method is called ELISA (enzyme-linked immunosorbent assay)3.

If the test comes back positive, an additional sample is put through a trial that utilizes spectrometry or chromatography. The techniques mentioned above are much more accurate in comparison to the ELISA method and are usually used for confirmation.

Finally, the solution is then tested for concentration levels of THCA. When it comes down to the confirmation threshold, it’s about 0.1 picograms per milligram of hair. In other words, if they find anything above the said threshold, it’s safe for them to conclude that you’ve been using marijuana in the past 90 days.

Can You Beat A Hair Strand Test?

While it’s certainly within the realm of possibilities, it’s not always an easy thing to do. There are several methods you can use to beat a hair test, but none of them are guaranteed to work.

Using detox shampoos is probably one of your safest bets. There are numerous products available on the market, but the vast majority of them are not worth the effort. However, there are a few that might yield some good results. In case you’re interested in a more in-depth analysis, take a moment and check out our article.

As far as the alternatives go, the Macujo and Jerry G methods are somewhat useful to a certain extent. While they are more or less DIY solutions, they have a specific success rate nonetheless. Shaving it all off is another solution, but it’s not an efficient one, and it fails to deliver in most cases.

Does Testing Vary Depending On Labs?

How Long Does Marijuana Stay In Your Hair? 3Contrary to popular belief, testing your hair in different labs will yield different results because not all labs follow the same protocol. Three most commonly used companies all use different screening methods.

Quest Diagnostics utilizes the so-called EIA testing, which is regarded as the most inaccurate one of those above three. Therefore, in case you’re anxious about passing a test, getting tested by Quest Diagnostics might end up being a benefit.

Psychemedics uses the ELISA tests which are designed to isolate the metabolites and are therefore significantly more accurate in comparison to EIA. As we mentioned, if you’re facing an ELISA test, your chances of passing are quite slim (in case you’re a regular user).

What Affects Drug Screen Results?

Several factors decide whether you’ll pass or fail the test. The ones that are NOT relevant are: your height, age, and weight. Contrary to popular belief, these parameters hold zero merits when it comes to detection success. You’ll face the same chances regardless of how tall or old you are.

However, the factors that can affect the overall outcome are your hair type and metabolism. In other words, people who have thicker and darker hair have less chance to pass the test. That being said, these factors play a minuscule role in the whole equation and are likely not going to be the deciding factor in the end.

Detection tests are very accurate and hair type and thickness while relevant isn’t essential for the accuracy of the screening whatsoever. In other words, don’t put your hopes up too high.

What Kind Of Errors Are Possible?

How Long Does Marijuana Stay In Your Hair? 4While follicle tests tend to be pretty accurate, the False Positive result is a legitimate concern4. The False Positive is one of the reasons why most people don’t believe much in these kinds of tests.

There are a lot of variables in play, which makes hair testing somewhat controversial and inaccurate. For example, it’s not completely clear whether hair can get contaminated by being exposed to marijuana smoke. There were instances when non-users were tested, and the results came back positive due to them being exposed to pot smoke5.

As we mentioned previously, hair color and thickness are also a part of the reason for false positives. It turns out that melanin content from your hair can affect the test outcome. It’s also well-known that gray hair tends to cause a false positive for reasons that are yet to be discovered.

The growth rate is also a factor here, meaning you can fail the test even if you were clean for the past 90 days in case your hair grows slowly. As far as this particular problem goes, there is little to no solution to it apart from simply cutting the hair off altogether.

The Conclusion

It’s important to point out the fact that it’s not easy to pass a follicle test. While there are several solutions available, they are hardly ideal. Most of them should be your last resort before facing a screening. The best practice is to refrain from using marijuana for at least three months before testing to safely pass it.

In case it’s too late to think about abstinence, we would recommend detox shampoos as they are probably the safest way of getting clean for the test. The Macujo and Jerry G methods may yield some good results, but they are far from being consistent. It’s more of a shot in the dark than it is a hard-written guarantee.

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