Now, looking to control its population’s growing dependence on methamphetamines, Thailand is attempting to legalize kratom, which it had originally banned 70 years ago. (...) With kratom’s legal status under review in Thailand and U.S. researchers delving into the substance’s potential to help drug addicts, Scientific American spoke with Edward Boyer, a professor of emergency medicine and director of medical toxicology at the University of Massachusetts Medical School. Boyer has worked with Chris McCurdy, a University of Mississippi professor of medicinal chemistry and pharmacology, and others for the past several years to better understand whether kratom use should be stigmatized or celebrated.