I bought the "kratom is non-addictive and can improve your life" line fully as a teenager. What ensued was indistinguishable from a full blown opiate addiction. I ended up in in-patient detox to finally quit and, five years later, have not regained all that I had lost during that time.
Just because kratom has a high threshold for overdose does not mean it is not an opioid.
Edit: Keaton != Kratom