In a July 2019 study by Binghamton University, State University of New York suggest that, “…kratom is not reasonably safe and poses a public health threat due to its availability as an herbal supplement.” Professor William Eggleston said, “Although it is not as strong as some other prescription opioids, kratom does still act as an opioid in the body … In larger doses, it can cause slowed breathing and sedation, meaning that patients can develop the same toxicity they would if using another opioid product. It is also reported to cause seizures and liver toxicity. Kratom may have a role in treating pain and opioid use disorder, but more research is needed on its safety and efficacy. Our results suggest it should not be available as an herbal supplement."
By English Wikipedia user Ingenium, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4653775