Pronunciation: kra-tem
Generic name: kratom
Dosage form: capsule, tablet, powder, liquid

Medically reviewed by Melisa Puckey, BPharm. Last updated on Mar 1, 2024.

What is Kratom?

Kratom is a herbal substance that has a stimulant and opioid-like effect. Kratom stimulant effects include alertness, rapid heart rate, and increased energy. Kratom can also cause effects such as relaxation, confusion, and pain relief similar to opioids and sedatives effect. How kratom affects each person depends on how much is taken, its strength or concentration, how it is taken (capsules, powder, tea), and the person's medical conditions and drug-taking history.

Kratom products are made from leaves from Mitragyna speciosa, a tree native to Southeast Asia. Kratom is usually taken as raw plant material either in a capsule, in powder form mixed into drinks or food, tea made with leaves, or as liquid kratom extract.Kratom’s common or street names are Thang, Krypton, Kakuam, Thom, Ketum, Biak-Biak (common name in Thailand), Mitragyna speciosa, mitragynine extract, biak-biak, cratom, gratom, ithang, kakuam, katawn, kedemba, ketum, krathom, krton, mambog, madat, Maeng da leaf, nauclea, Nauclea speciosa.

In the US, kratom has been used as an alternative agent for muscle pain relief, diarrhea, and as a treatment for opiate addiction (such as prescription narcotics or heroin), and withdrawal. However, its safety and effectiveness for these conditions has not been clinically determined.

Kratom and the FDA

The FDA notes it has no scientific data that would support the use of kratom for medical purposes. In addition, the FDA states that kratom should not be used as an alternative to prescription opioids, even if using it for opioid withdrawal symptoms. FDA encourages more research to better understand kratom’s safety profile, including the use of kratom combined with other drugs. At this time FDA has said that Kratom is not appropriate for use as a dietary supplement.

Effective, FDA-approved prescription medications, including buprenorphine (Sublocade), methadone, naltrexone (Vivitrol), and buprenorphine and naloxone (Suboxone) are available from a health care provider, to be used in conjunction with counseling, for opioid withdrawal. Also, they state there are also safer, non-opioid options for the treatment of pain.

In 2018 the US Centers for Disease Control and Prevention (CDC) reported it was investigating a multistate outbreak of 28 salmonella infections in 20 states linked to kratom use. They noted that 11 people had been hospitalized with salmonella illness linked to kratom. Those who fell ill consumed kratom in pills, powder or tea.

Is kratom legal?

Kratom is not controlled under the Controlled Substances Act but there may be some regulations or prohibitions against the possession and use of kratom in some states. The American Kratom Association is a lobbying and advocacy group in support of kratom use. The American Kratom Association reports that there are a number of misconceptions, misunderstandings and lies floating around about Kratom. They advocate to "fight anti-kratom legislation across the United States."

The FDA continues to seize adulterated dietary supplements containing kratom. Seized brand names have included: Boosted Kratom, The Devil’s Kratom, Terra Kratom, Sembuh, Bio Botanical, and El Diablo. There are no currently no FDA approved uses for kratom.

How does kratom work?

As reported in February 2018, the FDA has confirmed from analysis that kratom has opioid properties. More than 20 alkaloids in kratom have been identified in the laboratory, including those responsible for the majority of the pain-relieving action, the indole alkaloid mitragynine, structurally related to yohimbine. Mitragynine is classified as a kappa-opioid receptor agonist and is roughly 13 times more potent than morphine. Mitragynine is thought to be responsible for the opioid-like effects.

Kratom, due to its opioid-like action, has been used for treatment of pain and opioid withdrawal. Animal studies suggest that the primary mitragynine pharmacologic action occurs at the mu and delta-opioid receptors, as well as serotonergic and noradrenergic pathways in the spinal cord. Stimulation at post-synaptic alpha-2 adrenergic receptors, and receptor blocking at 5-hydroxytryptamine 2A may also occur. The 7-hydroxymitragynine may have a higher affinity for the opioid receptors. Partial agonist activity may be involved.

Additional animal studies have suggested that these opioid-receptor effects may be reversible with the opioid antagonist naloxone.

Time to peak concentration in animal studies is reported to be 1.26 hours, and elimination half-life is 3.85 hours. Effects are dose-dependent and occur rapidly, reportedly beginning within 10 minutes after consumption and lasting from one to five hours.

How does kratom make you feel?

Most of the psychoactive effects of kratom have evolved from anecdotal and case reports. Kratom has an unusual action of producing both stimulant effects at lower doses and more CNS depressant side effects at higher doses.

• Stimulant effects manifest as increased alertness, boosted physical energy, talkativeness, and a more social behavior.
• At higher doses, the opioid and CNS depressant effects predominate, but effects can be variable and unpredictable.

Reviews from consumers and the public who have used kratom report lessened anxiety, stress, and fatigue, pain relief, sharpened focus, and relief of withdrawal symptoms. Beside pain, other anecdotal uses include as an anti-inflammatory, antipyretic (to lower fever), antitussive (cough suppressant), antihypertensive (to lower blood pressure), as a local anesthetic, to lower blood sugar, and as an antidiarrheal. It has also been promoted to enhance sexual function. It's important to note that none of these uses have been studied clinically or are proven to be safe or effective.

It has been reported that opioid-addicted individuals use kratom to help avoid narcotic-like withdrawal side effects when other opioids are not available. Kratom withdrawal side effects may include irritability, anxiety, craving, yawning, runny nose, stomach cramps, sweating and diarrhea - all similar to opioid withdrawal.

Mixing kratom, other opioids, and other types of medication can be dangerous. Kratom has been shown to have opioid receptor activity, and mixing prescription opioids, or even over-the-counter medications such as loperamide, with kratom may lead to CNS depression and serious side effects.

Related: Kratom: Unsafe and Ineffective

How widely is kratom used?

On the Internet, kratom is marketed in a variety of forms, including kratom capsules, kratom drinks, kratom tea, raw leaf, powder, gum, pressed into tablets, and as a concentrated extract. In the US and Europe, it appears its use is expanding, and recent reports note increasing use by the college-aged population.

The DEA states that drug abuse surveys have not monitored kratom use or abuse in the US, so its true demographic extent of use, abuse, addiction, or toxicity is not known. However, as reported by the DEA in 2016, there were 660 calls to U.S. poison centers related to kratom exposure from 2010 to 2015.

In 2019, the FDA warned several manufacturers over false claims that their products containing kratom can treat or cure opioid addiction. The companies also made unproven claims for treatment for pain, depression, anxiety and cancer.

What are kratom side effects?

Kratom side effects include sedation, nausea, sweating, dry mouth, increased urination, loss of appetite, itching, constipation, dizziness, and confusion.

Case reports also describe the following kratom side effects: addiction, withdrawal, hypothyroidism, liver injury, aching of muscles and bones, and jerky limb movements.

Kratom addiction and chronic use have led to cases of psychosis with hallucinations, delusion, and confusion. High-dose use may lead to fast heart rate (tachycardia) and low blood pressure (hypotension). Tremor, anorexia, and weight loss are other possible side effects of long-term use.

Seizures have been reported when kratom was combined with modafinil in at least one case report. The DEA has also reported seizure adverse events with recreational kratom use.

A case series (Kronstad and colleagues) described a fatal drug interaction with kratom. A substance dubbed “Krypton” - a mixture of mitragynine and a metabolite of tramadol - was found post-mortem in nine people in Sweden over a one-year period. Tramadol, an opioid-like prescription pain drug, was most likely added to kratom to boost its narcotic-like effect.

Related/similar drugs

Does kratom cause liver injury?

In 2019, researchers published information that liver injury is a possible side effect of kratom use. They reviewed 404 cases of liver damage from dietary supplements. Eight of the cases, which occurred between 2007 and 2017, were tied to kratom, and the product was used two to six weeks before signs of liver damage appeared. Five patients had jaundice (a yellowing of the skin); six had itching; five had abdominal pain, and three had fever. Six patients were hospitalized, and all got better without the need for a liver transplant.

Is kratom deadly?

In November 2017 and February 2018, the FDA issued a public health advisory about deadly risks associated with kratom. There have been at least 44 reports of kratom-related deaths, sometimes used in combination with other illicit drugs, prescription drugs, or over-the-counter agents such as loperamide (Imodium).

• The FDA's analysis from February 2018 included 44 reported deaths associated with the use of kratom. Deaths reported by the FDA have involved one person who had no historical or toxicologic evidence of opioid use, except for kratom.
• In addition, reports suggest kratom may be used in combination with other drugs that have action in the brain, including illicit drugs, prescription opioids, benzodiazepines and over-the-counter medications, like the anti-diarrheal medicine, loperamide (Imodium AD).

As with many herbal alternatives, designer drugs, or illicit products sold on the Internet, the possibility exists that kratom may also be contaminated with illegal drugs, black market prescription medications, or even poisonous products. Consumers should avoid buying unknown drug products from the Internet. When combined with other drugs -- recreational, prescription, or alcohol -- the effects of kratom are unknown and may be dangerous.

Is kratom addictive?

Kratom is well-known to be addictive, as found with traditional use by natives over many years in Southeast Asian countries. Withdrawal effects similar to narcotic withdrawal and drug-seeking behaviors have been described in users in Southeast Asia. Many Southeast Asian countries have restricted the use of kratom due to the potential for abuse.

The fact that kratom is derived from a plant should not lead consumers to be believe it 100% safe and "all-natural". While certainly not all botanicals have dangerous properties, drugs with dangerous effects can come from botanicals, for example, heroin (opium poppy), cocaine (coca leaves), and nicotine (tobacco).

Will a drug test identify kratom use?

Currently, kratom is not included in standard drug screens in the US. Kratom tests are available for screening but are not widely available.

Bottom Line

• Kratom, an herbal product that originated in Southeast Asia, is being used in the US to ease anxiety, treat chronic pain and to reverse opioid withdrawal symptoms; often purchased over the Internet. Recreational use may be on the rise, and it is legal in many US states, but illegal in others.
• Kratom has opioid properties. Mitragynine is classified as a kappa-opioid receptor agonist and is roughly 13 times more potent than morphine. Mitragynine is thought to be responsible for the opioid-like effects.
• According to the FDA, deaths with kratom use have occurred, the scientific literature has disclosed serious concerns regarding the toxicity of kratom in multiple organ systems, and kratom affects the same opioid receptors as morphine.
• The FDA continues warn consumers not to use any products labeled as containing kratom.

The primary psychoactive component, mitragynine, is many times more potent than morphine. DEA lists kratom as a drug of concern. Placing kratom into schedule I would place it in the same category as heroin, LSD or marijuana, and prevent access for medical research, a concern for many experts, consumers, and advocacy groups. Lack of quality scientific evidence confounds the evaluation of the safety of kratom. Concerns also exist that the general public would not be able to identify or confirm the quality or purity of kratom from any Internet source.

Concerning reports continue to surface with kratom. Liver toxicity, heavy metal contamination and retail marketing of the product with false claims are some of the most recent issues. Heavy metals have included significant levels of lead and nickel at concentrations that exceed safe exposure for oral daily drug intake. In addition, consumption of kratom can lead to a number of health impacts, including, among others, respiratory depression, vomiting, nervousness, weight loss and constipation.

Health care professionals and consumers should report any adverse events related to products containing kratom to the FDA’s MedWatch program.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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