Toxicity
Can kratom kill you? The short answer is that if your were really determined to do so, perhaps it could. But it appears that it would be extremely difficult to take a lethal dose of the pure, unadulterated leaf, in the absence of other drugs. A recent study attempted to establish the lethal dose (LD50) of two of the primary alkaloids, mitragynine and 7-hydroxymitragynine, in mice. They did succeed in finding a lethal doses of these purified compounds when injected, but found no lethal dose of 7-hydroxymitragynine when given orally. The lethal oral dose of mitragynine was 547.7 mg per kilogram of body weight. A gram of dried kratom leaf contains about 12-21 mg of mitragynine, so on this basis, the lethal dose of dried kratom leaf for a 65 kg human would be about 1,695 gm, or about 3.7 lbs!
It is important to remember that animal studies are sometimes quite inaccurate when applied to humans, so the results of this mouse study can only be taken as another piece of suggestive evidence. Likewise, studies of isolated compounds are a poor model for the complex mixture of substances in a raw, unprocessed herb.
Very few deaths have been clearly attributed to kratom, and of the small number that have been associated with the plant, the vast majority involve one, or multiple, other drugs, or involve concentrated extracts.
Cases have been reported of individuals developing liver toxicity (cholestatic jaundice) after taking higher doses of kratom. “The hepatotoxicity reports are also very rare and mostly linked to long-term kratom consumption or to its excessive intake.” This appears to be particularly true of individuals with a prior history of heavy alcohol consumption whose livers may have diminished capacity.
Impaired Coordination
Kratom may cause mild impairment of coordination/slowing of the reflexes. I have not seen any studies that specifically address this issue.
Interactions
Not much is known about interactions between kratom and other medications, but there are studies indicating that it may affect the enzymes involved in breaking down some medications. It would be very wise to exercise caution if taking any medications concurrently with kratom.
Dependance/Addiction
There is a risk of dependence with kratom, though the general consensus is that this is much more likely to occur with sustained use at high doses. The European Monitoring Centre for Drugs and Drug Addiction states: “Regular kratom use may produce dependence. The withdrawal symptoms in humans are relatively mild and typically diminish within a week. Craving, weakness and lethargy, anxiety, restlessness, rhinorrhea, myalgia, nausea, sweating, muscle pain, jerky movements of the limbs, tremor as well as sleep disturbances and hallucination may occur. Treatment, if needed, may include dihydrocodeine-lofexidine combination, non-steroidal antiinflammatory agents, antidepressants and/or anxiolytics.”
A recent study examined withdrawal symptoms among 150 chronic kratom uses in Malaysia. They found that 70% experienced mild anxiety after discontinuing kratom, with 30% reporting moderate anxiety. Depression was also reported, with 81% reporting mild depression, and 19% moderate depression. Physical symptoms of withdrawal, including muscle and body aches, watery eyes, runny nose and decreased appetite were found to last an average of 2.8 days, with severity dependent upon how much was consumed. The psychological symptoms were found to last up to 3 weeks in chronic users. “Our results indicated that cessation from long-term and chronic kratom tea consumption (≥ 4 glasses) was not associated with significant or severe anxiety and depression symptoms among traditional kratom users.”
Kratom abuse in Ramathibodi Poison Center, Thailand: a five-year experience. This study, from a five year period at a facility in Thailand indicates that there are some issues with (withdrawal (12 cases) and toxicity (40 cases), “…the common presenting symptoms [of withdrawal] were myalgia (33.3%), insomnia (16.67%), fatigue (16.67%), and chest discomfort (16.67%). There were no deaths. An important note is that one of the withdrawal cases was a baby born to a kratom-using mother. This suggests that kratom should not be used in pregnancy, as its alkaloids apparently cross the placental barrier.
Respiratory Depression
Kratom reportedly does not cause the respiratory depression typically seen in opiates.