How Long Does Kratom Stay in Your System?

Ultimately, it depends. Kratom does not remain detectable in your body for a set amount of time. Various factors determine the duration, including how often you consume kratom and how much you take. Age, liver and kidney health, and metabolism speed can all have an impact, too.

I will start by examining how long kratom stays in your system before discussing how this relates to drug tests. Let’s do it. 

Kratom consists of numerous alkaloids that account for the herb’s unusual effects. Mitragynine and 7-hydroxymitragynine (7-HMG) are the most prominent of these alkaloids. And while the effects of mitragynine and 7-HMG wear off within hours, their metabolites can hang around for some time.

Unsurprisingly, some people are alarmed about their historic kratom usage coming to light. Sure, kratom is federally legal, but not everywhere or everyone looks upon it favorably. For instance, the Department of Defense prohibits active military personnel from taking kratom.

Having a ballpark figure of how long kratom remains in your system can help you plan ahead and start detoxing in advance. 

Several factors influence how long kratom stays in your system. Some of these you can control, others you can't. Let's go over them now. 

The potency of your kratom product affects how long the alkaloid metabolites linger in your system. Inevitably, higher-strength products pump more alkaloids into your body, which take longer to metabolize and eliminate. 

Regular kratom usage and high dosages lead to a buildup of alkaloids in your system. Essentially, you are topping up your kratom levels faster than your body can flush them out.

Even if you completely stop taking kratom, it could be weeks before alkaloid metabolites are no longer detectable in your system. In contrast, if you only consume kratom occasionally and stick with low dosages, it will take much less time for your body to become alkaloid-free. 

Age: Younger people typically have a faster metabolism speed than older people, which can reduce the time that kratom stays in your system. That said, being young does not guarantee a fast metabolism speed, much like being old doesn’t condemn you to a slow one.

Liver and Kidney Health: The liver and kidneys play a role in kratom alkaloid metabolization and elimination. Compromised liver or kidney health can adversely affect your ability to clear kratom from your system, meaning metabolites remain detectable for longer.

Hydration: Staying well-hydrated promotes optimum kidney functioning, which is vital to removing substances from your body, whether that be kratom or something else. Dehydration can slow the rate at which your system clears kratom, prolonging its presence in your body.

Mitragynine is the most abundant indole alkaloid in kratom and the compound to be most wary of. Frustratingly, there is little scientific research on the substance, and most studies that have examined mitragynine’s pharmacokinetics have taken place in rodents.

However, a 2016 study conducted by University of Florida scientists and published in the International Journal of Legal Medicine gave us a glimpse into mitragynine’s half-life in humans. This statistic describes how long it takes for the amount of an active substance in your system to reduce by 50%.

The study involved 10 healthy volunteers taking mitragynine in whole-leaf kratom form. The researchers found that mitragynine has a half-life of between seven to 39 hours in humans, which is much longer than the half-life of most opioid agonists.

From this, we can deduce that kratom lingers in your system for significantly longer than opioid drugs. The University of Florida study also revealed that, when taken orally, mitragynine reaches peak plasma concentration within 60 minutes of consumption.

The bottom line for those not well-versed in scientific jargon: mitragynine appears to hang around! And there is a massive difference between a seven-hour half-life and a 39-hour half-life! It would be unwise to read too much into the findings.

Complicating matters, other studies exploring mitragynine’s half-life have produced significantly different results.

A study published in the Brain Research Bulletin estimated mitragynine’s half-life at 9.43 hours. However, a 2015 paper featured in Drug Design, Development, and Therapy had it at 3.85 hours. But such differences in results happen frequently in scientific research. 

It is impossible to provide an estimate without settling on a half-life for mitragynine. Thirty-nine hours is an outlier, so let’s discard that and take an average of the three other half-life statistics mentioned. Seven hours, 9.43 hours, and 3.85 hours average to a 6.76-hour half-life.

While not an exact science, it is sufficient for our purposes. Let’s simplify things by assuming that mitragynine’s half-life is seven hours.

In this case, more than 99% of your kratom dosage will be eliminated from your system after 48 hours. However, that doesn’t account for other factors affecting mitragynine’s half-life.

Of course most of these concerns over how long kratom remains in your system come back to one question: does kratom show up on a drug test? In many cases, it doesn't. However, there are caveats and exceptions to be aware of.

Let’s start by analyzing the possible drug tests you may encounter.

There are several ways of potentially detecting kratom metabolites in your system. But any of these could become more common as kratom grows in prominence.

Urine testing: Most employers choose urine tests to check for substance use. Depending on how much you take, kratom could remain detectable in your urine for more than a week. But testing specifically for kratom is rare since the herb is not typically an illicit substance.

Blood testing: This type of testing is effective at determining whether a substance is currently active in your system. And kratom could remain detectable in your blood for days if you are a regular and heavy user. A blood test may be required if you are involved in a workplace accident.

Saliva testing: Nowadays, some employers prefer saliva (oral fluid) testing to urine testing. In theory, these tests could be designed to detect kratom usage, with metabolites likely detectable for a few days. But I am yet to see any evidence of this happening.

Hair testing: Testing hair follicles is the most effective method of detecting historical substance use. Kratom metabolites could remain in hair follicles for several weeks (or even months!). Thankfully, there are no current signs of hair tests being used to check for kratom. 

Firstly, as a federally legal substance, kratom is not subject to the same drug testing scrutiny as cannabis, cocaine, psychedelics, and other controlled substances. Therefore, most people can consume kratom without issue.

Indeed, the urine tests used by most employers cannot detect kratom alkaloids. A separate test would be required to flag up kratom use, which is often more hassle than it is worth.

But if you live in a state where kratom is banned, the company you work for may have a policy prohibiting employees from taking kratom. Military service members could also be tested, given the Department of Defense bans its use.

However, while the means are technically there to detect kratom usage via a drug test, the risk of getting targeted and caught is extremely low.

Indeed, kratom products causing a false positive drug test are a bigger worry. And there is a concerning amount of anecdotal evidence showing that this happens. Check out this Reddit post as an example.

A false positive could occur due to a poor-quality test mistaking kratom alkaloids for opioids. You can resolve this situation by requesting that your sample be sent to a laboratory for more rigorous analysis.

However, testing positive because of adulterated kratom could put you in a stickier spot. Cowboy companies and scammers have no qualms about adding anything to their kratom products, from synthetic alkaloids to actual opioids.

You may struggle to state your case to an employer if you have an illicit substance in your system, even if you knew nothing about it. This just emphasizes the importance of buying high-quality, lab-tested kratom from transparent and respected brands.

The lack of concrete evidence makes it tricky to work out how long kratom stays in your system. But we can assume that kratom does not linger for more than a few days in most cases.

Given this uncertainty, it is a relief that most people don’t need to worry about the issue. Testing for kratom use is rare and only occurs in certain lines of work. I hope the relaxed approach most employers have toward kratom continues.