Kratom Guides

What Is Kratom? Uses, Side Effects, & Safety

Kratom is a plain-looking evergreen tree originating from Southeast Asia. It’s used as a stimulant in lower doses and a sedative and painkiller in higher doses.

Wade Paul

Medically reviewed by Dr. Devin Carlson

Written by Wade Paul5 months ago

What Is Kratom? Uses, Side Effects, & Safety

What Is Kratom?

Kratom (Mitragyna speciosa) is a member of the Rubiaceae family of plants — which makes it a close relative of the coffee plant (Coffea spp.).

Much like its cousin, kratom is a powerful central nervous system stimulant. It’s used to boost both physical and mental energy.

Kratom has been a popular herb among laborers in Asian countries as a way to prevent burnout since the early 19th century — but it’s traditional medical use likely extends much further than that. 

The effects of kratom are unique — it has some qualities that are stimulating, others that are sedative or anxiolytic. The dose of kratom determines its effects. High-dose kratom is a powerful painkiller and euphoric similar to opiate pain medications.

In lower doses, the kratom plant only offers mild pain-relief but activates the central nervous system to make users feel more alert and energized.

How is Kratom Used?

The Mitragyna speciosa leaves are chewed fresh, smoked, or powdered and brewed as a strong tea.

Some suppliers offer kratom extracts — which are made by removing everything but the active ingredients of the kratom resin.

Outside Southeast Asia, the most common way of consuming the plant is to mix the dried, powdered leaves with a glass of water. This produces a strong and bitter drink. It’s unusual for someone to enjoy the flavor of kratom, but this isn’t why it’s used.

Most users will flavor the beverage with honey or sweetener to help mask some of the disagreeable flavors and wash the rest back as quickly as possible.  

What’s The Dose of Kratom?

There’s no one-size-fits-all when it comes to the best dose of kratom. There are a lot of variables that affect the dose — including strain selection, the freshness of the leaves, your individual weight, and the desired effects.

We can split the dose of kratom into two different camps:

  • Low-Dose Kratom (2–6 grams of dried powder)
  • High-Dose Kratom (6–12 grams of dried powder)

If it’s your first time using kratom, it’s best to start at the lowest dosage range and increase gradually over several sessions once you know how your body responds.

If you want a more precise estimate on the ideal dose of kratom for your body — aim to take around 0.03 grams per pound of bodyweight for the stimulating effects or a dose of 0.06 grams per pound for the sedative and painkilling effects.

For reference, a teaspoon of dried kratom powder is around 2.5 grams of powder, and a tablespoon is roughly 7 grams.

What Does Kratom Feel Like?

Kratom is a complex plant — there are 16 key ingredients in the leaves, each with their own set of effects. The ratios of these compounds can change from one strain to another, giving each one a unique effect profile.

The dose also affects how kratom feels.

Low doses are stimulating. It feels similar to coffee but less likely to result in negative side-effects like anxiety or jitteriness. It also has a mild euphoric action at this dose — helping to uplift the mood and promote more clarity of thought. These doses are used as a nootropic or stimulant to boost physical and mental energy and stamina.

Around the 7-gram dosage mark — the effects of the herb does a complete flip. At higher doses, kratom has a sedative action. Users feel relaxed, care-free, and lazy. These doses are most useful for supporting sleep, easing anxiety, and alleviating chronic pain or muscle tension.

Other effects of kratom at all doses include mild visual effects, increased empathy, and a warming sensation in the body.

It’s a popular aphrodisiac — increasing sexual arousal and improving erectile function. Some people find the sexual stimulant effects of kratom begin to taper off with higher doses.

How Long Does Kratom Last?

The effects of kratom take about 30 minutes to take effect and peak around the 1-hour mark. People who use kratom on an empty stomach report an even faster onset of effects — but this also increases the chances of experiencing side effects.

In total, the effects of kratom last around 3 or 4 hours.

What Are The Benefits of Kratom?

Kratom has a long history of medical uses that range from infection and bladder disease, fevers, diarrhea, diabetes, fatigue, and mental health disorders.

Today, kratom is primarily used for its nootropic and painkilling benefits. Some users take the herb as an alternative to prescription painkillers or as a buffer to help wean themselves off addictive opiate medications.

Kratom For Pain

Although there are few studies to back up the potential medical uses of kratom, it’s considered one of the most effective herbal pain relievers — second only to opium.

Learn more about how to use kratom for pain relief.

Withdrawal symptoms from kratom are also milder and short-lived.

Kratom For Addiction & Withdrawal

A 2008 case study explored the use of kratom for ameliorating withdrawal symptoms of a recovering opiate addict [3]. The patient in this study reported that the withdrawal period was considerably less intense compared to prescription painkillers but took a little longer to recover completely.

Prior to the study, the patient was addicted to hydromorphone. He quit the medication abruptly and was able to avoid withdrawal by using kratom four times per day. He reported kratom was effective for both preventing withdrawal symptoms and alleviating the chronic pain that prompted him to use the painkillers in the first place.

Kratom is currently being explored as an alternative to methadone as the standard treatment for opiate addiction in developing countries due to its impressive safety profile and widespread availability.

Kratom As A Nootropic

Besides strictly therapeutic qualities, kratom is also considered by brain hackers an effective tool for personal growth. It’s used short-term to boost mental energy and focus, and long-term to enhance overall mental endurance and stamina.

Similar to other natural psychoactive substances, kratom can also catalyze deep emotional, psychological, and interpersonal healing. It’s reported to liberate users from the constraints of everyday patterns in behavior. Some suggest the herb can divert attention to neglected problems by promoting introspective thoughts — especially at higher doses. 

Kratom For Anxiety

Kratom has been shown to have clear antidepressant and anti-anxiety benefits in animal studies [4]. Mice treated with mitragynine were found to have lower concentrations of corticosterone (one of the key stress hormones) in their blood.

Risks & Side-Effects of Kratom

Kratom is generally considered safe — but there are some caveats. We need more long-term clinical studies before we can jump to any definitive conclusions.

So far, we know that mitragynine — one of the active ingredients in kratom — demonstrates very little toxicity, even in large doses. Researchers have reported no lethal effects in rats administered very high doses (1000 mg/kg) of kratom leaf or 806 mg/kg of pure mitragynine (taken orally) [5].

With that said, there are still plenty of risks and side effects to be aware of when using kratom.

Kratom Adulterants

For one, kratom products vary in quality — different preparations may contain dangerous adulterants. Some samples of kratom have been found to contain prescription painkillers like fentanyl, hydrocodone, or morphine.

In Sweden, nine people died from a “boosted kratom formula” called Krypton. This product contained a combination of kratom, caffeine, and O-desmethyltramadol. Other kratom products have been found to contain significantly less kratom than advertised on their packaging.

Kratom & Drug Interactions

Kratom should not be mixed with any other medications. There have been reports of patients mixing kratom with stimulant medications such as modafinil that have led to seizures.

It’s also particularly dangerous to mix kratom with alcohol or other central nervous system depressants — especially with higher doses.

If you’re taking any illicit or prescription medications, it’s important you first speak with your doctor about using kratom before trying it yourself.

What Are The Side-Effects of Kratom?

  • Hyperpigmentation
  • Insomnia
  • Nausea
  • Low libido
  • Poor appetite
  • Dizziness
  • Loss of muscle coordination
  • Tremors or muscle contractions
  • Low blood pressure
  • Itchiness in the skin
  • Seizures

Can You Overdose on Kratom?

Although no study has identified a lethal kratom dosage in humans, one 2019 study found the lethal dose in mice.

It was actually a lethal dose of extracted alkaloids injected intravenously. For mitragynine, a median lethal dose for 50% of the test population (LD50) was reported to be 27.8 mg per 1 kg of body weight. 7-hydroxymitragynine has a threshold of 24.7 mg/kg [8].

When consumed orally, the LD50 for mitragynine in mice was 547.7 mg/kg with no lethal dosage observed for 7-hydroxymitragynine.

These doses are far too high to reasonably achieve using oral forms of the herb. Only by injection is it possible to hit doses this high. Kratom produces severe nausea and vomiting long before reaching the toxic dose.

Is Kratom Addictive?

Yes, kratom can be addictive — but only with long-term use.

While the addictive nature of kratom is much milder than powerful pharmaceutical drugs, this herb can still result in changes to the opioid receptors that can lead to physical dependence. The longer you use kratom, and the higher the dose, the more likely you are to become dependent on the drug.

Long-Term Negative Health Effects of Kratom

The long-term safety of kratom has yet to be fully elucidated as well. Most of the long-term safety data we have available on the herb come from anecdotal reports only [6].

Users who were taking kratom regularly for two to eight weeks reported experiencing nausea, itching, dark urine, jaundice, and abdominal pain. These side-effects may indicate that long-term use of kratom also affects the liver. Heavy kratom users might have problems with over-pigmentation or darkening of the cheeks. In rare cases, high concentrations of alkaloids may cause kidney damage and compromise cardiovascular functions [7].

Kratom Active Ingredients

There are literally dozens of active ingredients in the kratom plant, each one producing a different set of effects. Most of the active ingredients are classified as either indole or oxindole alkaloids. They exert their painkilling, anxiolytic, stimulating, and nootropic benefits by binding and interacting with various neurotransmitters in the brain.

Each kratom strain has a different ratio of active ingredients — this gives each plant a unique set of effects. Some are more stimulating, others more sedative or painkiller. The difference in effects are the result of different concentrations of the active ingredients.

Roughly 90% of the active alkaloid content consists of just four compounds, but there are many others as well:

  1. Mitragynine — This is the most abundant constituent in most kratom strains, accounting for up to 66% of the total alkaloid content of the plant. It acts as a 5-HT2A receptor agonist, which is a similar mechanism of action used by psychedelics like LSD and psilocybin. It also targets the mu-opioid and kappa-opioid receptors.
  2. Paynantheine — The second most abundant alkaloid in kratom. Paynantheine acts as a smooth muscle-relaxant and opioid receptor agonist with relaxing effects.
  3. Speciogynine — The third most abundant alkaloid in kratom. It provides a great deal of the plant’s muscle-relaxant and anti-anxiety benefits.
  4. 7-hydroxymitragynine — Abundant in varying concentrations for different kratom strains but is most common in red-veined kratom strains. Acts through the mu-opioid receptors.

What Are The Different Types of Kratom?

As with most plants, there are many different strains of kratom — each with different characteristics.

What is a strain?

Whereas a species is a genetically unique plant with its own species name, a strain refers to the offspring of a plant that shares the same genetic makeup but differences in physical or chemical profiles. All kratom is the same species (Mytragyna speciosa), but there are many different strains within that species — such as Red Kali, Green Hulu, White Dragon, and many more.

There are three main categories for the different kratom strains based on the color of the leaf veins — red, white, and green.

While there’s a lot of variability within each category, it serves as a fairly reliable way of cataloging the different effects we can expect from each leaf type.

Red Vein Kratom Strains

Red vein kratom is generally more relaxing and sedating than the other types. It’s usually the best option for pain-relief and sleep-support. The red color is thought to be the result of the higher 7-hydroxymitragynine concentrations.

These strains are also some of the most fast-acting. You can start to feel the effects of most red-veined leaves within about 20 minutes.

Red-Vein Kratom Strains Include:

  • Red Jongkong Kratom
  • Red Asia Kratom
  • Red Kali Kratom
  • Red Elephant Kratom
  • Red Indo Kratom
  • Red Sumatra Kratom
  • Red Hulu Kratom
  • Red Malay Kratom
  • Red Thai Kratom
  • Red Horn Kratom
  • Red Borneo Kratom
  • Red Dragon Kratom
  • Red Bali Kratom

White Vein Kratom Strains

White vein kratom is generally thought to be the most stimulating option (with some exceptions).

It’s more popular among people who tend to take their kratom first thing in the morning, similar to a coffee. They’re rich in euphoric alkaloids, which make them a great option for boosting mood and motivation.

White-Vein Kratom Strains Include:

  • White Borneo Kratom
  • White Thai Kratom
  • White Bali Kratom
  • White Vein Kratom
  • White Maeng Da Kratom
  • White Indo Kratom
  • White Horn Kratom
  • White Elephant Kratom
  • White Dragon Kratom
  • White Sumatra Kratom
  • White Malay Kratom
  • White Jongkong Kratom

Green Vein Kratom Strains

Green-vein kratom is stimulating similar to white-vein — but with longer-lasting effects. They’re also much more abundant and therefore cheaper overall. These strains are usually quite balanced, offering a good array of sleep-supportive, anti-anxiety, and stimulating benefits.

Because of the high variability within the green-veined group, these strains are much more unpredictable. Some are more stimulating, others much more sedative.

Green-Vein Kratom Strains Include:

  • Green Malay Kratom
  • Green Maeng Da Kratom
  • Green Borneo Kratom
  • Green Hulu Kratom
  • Green Vietnam Kratom
  • Green Vein Kratom
  • Green Thai Kratom
  • Green Horn Kratom
  • Green Indo Kratom
  • Green Dragon Kratom
  • Green Sumatra Kratom
  • Super Green Malay Kratom
  • Green Kali Kratom
  • Green Bali Kratom

Is Kratom Legal?

Yes, kratom is legal in most (but not all) parts of the world.

Kratom, like many other mind-altering plants, has a checkered history with the legal system.

There seem to be three different philosophies a country can take towards the kratom plant:

  1. “It can be addictive, so it should be illegal!”
  2. “It’s much less addictive and dangerous than other opiates, so it should be legal!”
  3. “What the heck is kratom?”

Kratom Laws in North America

Kratom isn’t included in the United States federal list of controlled substances, although the DEA considers it adrug of concern.” This means it’s on their watch-list but not officially banned or regulated. If it becomes clear the herb is leading to issues with overdoses or addiction, they’ll likely step in to ban it nationwide.

However, as we’ve already covered, the potential for abuse with kratom is much lower than all other opioid medications, and it’s virtually impossible to overdose on the herb without injecting it — which is exceptionally rare, and there isn’t much point in doing it (it will make you feel like trash).

Most US states follow the federal guidelines involving kratom — which means it’s perfectly legal to order it online and use it without a prescription. A select few states have decided to ban the herb with their own state laws.

States that have banned kratom use:

  • Alabama
  • Indiana
  • Rhode Island
  • New Hampshire
  • Tennessee
  • Vermont
  • Wisconsin

In both Canada and Mexico, the herb is entirely legal — you can order it online or in-store without a prescription.

Kratom Laws in Asia & Australia

In Malaysia and Thailand, Kratom is also known as biak-biak, kakuam, ithang, thom/tom, and ketum. It’s so deeply rooted in the local culture that hardly anybody considers it a drug. Most people will turn to using kratom for pain-relief before going for prescription painkillers.

Indonesia still allows the use of kratom. In fact, they’re the primary exporter in all of Southeast Asia.

Other Southeast Asian countries have banned the substance — including Malaysia and Thailand.

Australia, Japan, Myanmar, New Zealand, Singapore, South Korea, and Japan have all since banned or regulated the use of kratom as well.

Kratom Laws in Europe

There’s a big difference in opinion on the kratom plant between different European countries. Some parts permit the sale openly; others have no mention of the herb — either good or bad — while others yet ban it with enforced jail sentences.

As of 2021, kratom is legal in the following European countries:

  • Austria
  • Belgium
  • Croatia
  • Czech Republic
  • Germany
  • Greece
  • Holland
  • Hungary
  • Moldova
  • Slovakia
  • Spain

In the UK, kratom remains illegal under the Psychoactive Substances Act. The plant and its active compounds are controlled by various bills in a number of EU member states, including Denmark, Poland, and Sweden.

Kratom Frequently Asked Questions

There’s a lot involved with this useful herb. If we were unable to answer your question, check out this faq, which we keep updated whenever we get a new question we haven’t answered. Feel free to drop us a line if there’s something in here we haven’t covered. We’d love to help!

1. Does Rotating Strains Prevent Tolerance?

Tolerance is one of the main concerns among people who use the plant on a regular basis.

One common misconception is that by using different strains, we can side-skirt the formation of tolerance to this plant.

Unfortunately, aside from a few anecdotal reports on Reddit, there’s no evidence to suggest this is true. The alkaloids are the same in each strain — the only difference is their ratio compared to each other.

2. Is Kratom Injectable?

According to a 2018 survey conducted by Ohio Substance Abuse Monitoring Network, 7 out of 10 kratom users admit they would shoot the drug if they had the opportunity.

It’s technically possible to inject kratom, and this is a common method of administering the herb to mice in medical research — however, it’s not practical in real-life applications.

Injecting the herb involves pharmaceutical-grade preparation, which makes it very expensive and hard to find. Secondly, it’s not an enjoyable way of using the plant at all.

The effects of injecting pure kratom alkaloids are rarely positive — often leading to severe side-effects and discomfort, such as the kratom wobble.

The bottom line is that while it’s technically possible, nobody injects kratom because it’s expensive, won’t offer you the core benefits, and will make you feel terrible.

3. Does Kratom Show Up On A Drug-Test

A drug test can only find what it’s looking for. This means if a compound isn’t specifically listed on the drug panel, it’s not going to pick it up.

If kratom is listed on the drug test, it will find it in the bloodstream. It can take over a week for kratom to clear out of the body completely, so if the test is given within that time frame, it will likely show up.

However, most companies, government agencies, or athletic associations ordering the drug test aren’t looking for kratom. The herb is completely legal in most parts of the world, so there’s no reason to look for it in the first place.

This could change if you’re currently living in a region where kratom is outlawed.

Kratom is unlikely to trigger a false positive for other opiate medications as well because the chemical structure of the active ingredients are very different from conventional pharmaceutical or illicit opiates.

4. How Long Does Kratom Stay in Your System?

There are conflicting results regarding the time kratom can be detected in urine [9]. Some say the body flushes kratom out of the body in as little as one day — while others claim it can stay in your system for upwards of two weeks.

Most experts agree kratom alkaloids are virtually undetectable in the blood by the second week after ceasing use.

As with just about any substance, the more often you use it, the longer it takes for it to be removed from the body.  

5. Can Kratom Lead to Psychological Trauma?

There’s some evidence suggesting a link between long-term kratom use and delusional behavior. While moderate use won’t cause psychological problems, some kratom users have developed anxiety after taking high doses for prolonged periods. The kratom “high” is usually mild and easy compared to many other psychoactive substances.

You should never use kratom or any other psychoactive substance if you or a close family member has a history of psychosis, bipolar disorder, or schizophrenia.

6. Where Can I Buy Kratom?

Kratom is available both locally and online. When searching for kratom near you, make sure to check out local vape shops, head shops, and specialty stores.  As mostly a buyer’s market, it offers a full range of options and a myriad of reviews. However, there’s also a lot of confusion and inconsistency.

If you want to get the best deals on high-quality kratom, we recommend finding a trustworthy online vendor. While we’re not saying that everyone listing kratom for sale actually knows their business, you can find many passionate vendors out there with knowledgeable customer service and premium-grade kratom powder.

7. Is It Legal To Grow Kratom At Home?

It’s legal to grow kratom wherever the herb isn’t banned.

The only things you need to get started growing kratom are some seeds or live plants — which you can order from most kratom vendors online along with the powder.

Kratom is a tropical plant, so you’ll need to give it lots of light and water and keep it in a nice warm spot in your house, away from the air conditioner, cool windows, or areas of the house that get a lot of breeze.

8. What’s The Best Way To Take Kratom?

The most common method of using kratom, by far, is the “toss and wash” method. This involves “tossing” back a spoonful of the raw powder and following it up with a big gal of water (the “wash” part).

The flavor of this herb is disagreeable. Even mixing it with a fruity juice does a poor job at masking the flavor. It’s best to just knock it back quickly and get it over with — sort of like ripping off a bandaid.

People who are apprehensive may choose capsules to avoid the taste altogether. The downside is that you’ll need to take several capsules to hit the effective dose of the herb.

Last but not least, you can brew your kratom powder as tea. Kratom tea is believed to have the fastest onset of all methods, and it doesn’t cause stomach upset. Keep in mind, the taste is still not going to be ideal with this method, but flavoring it with some honey can help.

9. Is it Safe to Take Kratom Resins, Extracts, & Tinctures?

Kratom extracts and resins are very potent. They’re safe to use but should only be attempted by those with a lot of experience using kratom. It’s easy to take too much of these concentrated extracts, which can make you feel nauseous and dizzy.

Start with a very low dose and increase gradually with each dose until you find what works for you.

Tinctures can be very hit or miss. Some are super potent, others much weaker. With practice, you’ll learn how to gauge the potency of the tincture based on the concentration listed on the bottle (such as 1:5, 2:1, or 10:1).

10. Can You Smoke Kratom?

Although stories of people smoking kratom aren’t unheard of, doing so won’t produce much of an effect. Heat destroys most of the psychoactive effects of the alkaloids in kratom. You’ll still feel the effects, but they’ll be much milder, and you’ll end up wasting a lot of the active ingredients in the herb.

11. Can I Microdose Kratom?

There are some people who have been posting results of their experiences microdosing kratom online. Users report having higher energy levels, better focus, and a stronger sense of health and wellbeing after using microdoses of kratom.

Currently, there are no clinical studies to back up these effects, and the long-term health implications of taking kratom on a daily basis still aren’t well understood.

12. Can Kratom Replace Any Medications?

Combining kratom with certain substances could potentially be dangerous. For example, when you mix kratom with opiates, you may suffer from fatal respiratory depression. Loss of consciousness and vomiting are also common side effects of such interactions. It’s not safe to replace your medications with kratom unless first getting guidance from your prescribing doctor.

Kratom is known to interact with oxycodone, hydrocodone, tramadol, DXM, and benzodiazepines, such as Valium, Xanax, and Klonopin.

Kratom and alcohol are not a good pairing due to alcohol’s depressant effects. It could result in respiratory failure due to cross-interaction. Some people use kratom instead of alcohol as a mild intoxicant — but never mix the two together.

Others use kratom to replace chemical stimulants like Adderall or even caffeine.

Kratom can also be used as an alternative to cannabis. The effects feel different, but the use-cases are very similar between these two plants. If you find you react poorly to marijuana and experience paranoia, anxiety, and insomnia — kratom may be worth a shot. Never mix kratom and marijuana together.

Summary: What Is Kratom & What Is It Used For?

Kratom is an incredibly useful plant. It’s one of the best herbal painkillers in the world and offers a unique dichotomy of stimulating and sedating effects depending on the dose. You can use kratom as a nootropic and stimulant like caffeine, or as a sedative and anxiolytic-like cannabis or kava.

Despite its health benefits, kratom is fairly controversial. It’s banned in several countries and listed as a “drug of concern” by the DEA. The worry is that because kratom works on the opioid receptors, it could be addictive.

While it’s true, consistent kratom use can develop tolerance and lead to addiction — which is why it’s safest to take regular breaks from kratom every couple of weeks at least. Compared to most opiate painkillers or sedatives, kratom is significantly safer. It’s much easier to prevent and reverse addictive tendencies to this herb than any other opiate medication.

References Cited In This Article:

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  2. Prozialeck, W. C., Jivan, J. K., & Andurkar, S. V. (2012). Pharmacology of kratom: an emerging botanical agent with stimulant, analgesic, and opioid-like effects. The Journal of the American Osteopathic Association, 112(12), 792-799.
  3. Boyer, E. W., Babu, K. M., Adkins, J. E., McCurdy, C. R., & Halpern, J. H. (2008). Self‐treatment of opioid withdrawal using kratom (Mitragynia speciosa korth). Addiction, 103(6), 1048-1050.
  4. Idayu, N. F., Hidayat, M. T., Moklas, M. A. M., Sharida, F., Raudzah, A. N., Shamima, A. R., & Apryani, E. (2011). Antidepressant-like effect of mitragynine isolated from Mitragyna speciosa Korth in mice model of depression. Phytomedicine, 18(5), 402-407.
  5. Ujváry, I. (2014). Psychoactive natural products: an overview of recent developments. Annali dell’Istituto superiore di Sanita, 50, 12-27.
  6. Swogger, M. T., Hart, E., Erowid, F., Erowid, E., Trabold, N., Yee, K., … & Walsh, Z. (2015). Experiences of kratom users: a qualitative analysis. Journal of psychoactive Drugs, 47(5), 360-367.
  7. Lu, J., Wei, H., Wu, J., Jamil, M. F. A., Tan, M. L., Adenan, M. I., … & Shim, W. (2014). Evaluation of the cardiotoxicity of mitragynine and its analogs using human induced pluripotent stem cell-derived cardiomyocytes. PLoS One, 9(12), e115648.
  8. Smith, L. C., Lin, L., Hwang, C. S., Zhou, B., Kubitz, D. M., Wang, H., & Janda, K. D. (2018). Lateral flow assessment and unanticipated toxicity of kratom. Chemical research in toxicology, 32(1), 113-121.
  9. Meireles, V., Rosado, T., Barroso, M., Soares, S., Gonçalves, J., Luís, Â., … & Gallardo, E. (2019). Mitragyna speciosa: Clinical, toxicological aspects and analysis in biological and non-biological samples. Medicines, 6(1), 35.