How Long Does Marijuana Stay in Your System? — Comparing Blood, Urine, Saliva, and Hair Testing

Whether we are trying to ease the symptoms of some ailments or just looking to relax after a hard day’s work, marijuana is the go-to remedy for many people around the world. However, the laws are fairly strict, especially in the US, where marijuana is still classified as a Schedule I controlled substance. So how long does marijuana stay in your system, and could it be detected through a test months after the last use? Read on to see what studies have shown regarding Mary Jane and its rather long-lasting effects.


How Long Does Marijuana Stay in Your System? — Factors That Impact Test Results 


Depending on the way we take it, marijuana’s, or rather, THC’s effects, become evident in as little as 15 minutes. It’s common knowledge now that smoking marijuana is the fastest way of experiencing its effects, as it only takes about 15 to 30 minutes for it to kick in. If we ingest marijuana, however, the effects may be delayed a bit. It can even take up to two hours to feel something.


Of course, if we take some Mary Jane just before a drug test, there’s no way we will pass it. However, if we use it only occasionally, it’s a good idea to know what will make it stay in our system for longer. The major factors that impact this are:


THC Dosage and Strength


Unfortunately, we cannot know for sure how much THC each dose contains, so most of the time, it’s purely a guessing game. If we are also taking a lot of marijuana, the THC percentage found in our bodies will naturally be higher.


Besides, THC has cumulative effects, meaning that the more we use, the more it builds up. Its metabolites get stored in our body fat and take a while to eliminate through urine or feces. Of course, if we have a higher fat concentration, we will likely metabolize it rather slowly.


Method of Administration


The effects of marijuana may be similar across the board, but there is a huge difference in how we metabolize it according to how we administer it. Evidently, edibles take longer to break down, so any marijuana taken in that form will remain in our system for longer. The effect comes on faster if we smoke or vape it. However, the THC levels will diminish swiftly in that case.


Age, Level of Physical Activity, and Sex


As mentioned, body fat (or our BMI) plays a significant role in how long marijuana sticks around. Besides that, we have to take into account our age and level of physical activity. Older or rather sedentary individuals usually have a slower metabolism. Because of that, marijuana may linger for longer in their case.


It’s also good to know that women may metabolize marijuana more slowly than men. Once again, that’s all thanks to the body fat percentage, which is usually higher in females.




Finally, dehydration may also play a role in passing or failing a drug test, as it can increase THC concentration. However, that doesn’t mean flushing the system would do much good. If anything, it would only dilute the urine.


How Long Does Marijuana Stay in Your System?




In general, marijuana doesn’t stay in the blood for long, so blood tests aren’t as reliable as urine tests. When inhaled, marijuana can be detected almost immediately in the bloodstream, and it remains there for one to two days




Urine testing is the most common because it can detect marijuana for 30 days or more in case of chronic, heavy smoking. If someone is a chronic user, they aren’t likely to pass a test, as THC keeps building up.


As a good rule of thumb, we ought to remember that marijuana may stay in urine for about three days after a single-use. Daily users, on the other hand, may have to wait for 15 days until it leaves their system.




Unfortunately for some, marijuana may be detectable in saliva up to 29 days if we’re chronic marijuana lovers. Occasional users needn’t worry too much, though; in their case, it is virtually non-existent in saliva after 24 to 72 hours.




Surprisingly enough, if someone gets a strand of our hair, they could theoretically determine if we have used marijuana in the past 90 days


Nevertheless, hair tests aren’t as reliable as one might think. For one, they cannot prove frequent usage or show how much marijuana has been used. On top of that, hair can be contaminated if we’re in contact with cannabis users or have to handle cannabis in some way. Essentially, we could get a false positive on a test by simply being in close contact with a marijuana user, as it can transfer via hands, sebum, sweat, and smoke.


Final Thoughts


So how long does marijuana stay in your system? Depending on how we ingest it, it’s possible to detect it for up to 90 days. Of course, it’s unlikely that we will have to take a hair sample test due to its unreliability. Still, it’s evident that if we don’t want to fail a drug test, it might just be better to steer clear of marijuana completely. It definitely tends to linger, which may pose an issue in our daily life, at the office, and if we ever have a brush with the law.

Leave a Reply

Your email address will not be published.