Kratom use as more than a "self-treatment".

(kratom) is increasingly used in the United States for its pharmacological effects. Kratom's relative novelty makes for a dynamic situation, such that use motivations are not firmly established and may be changing. Investigators and clinicians require frequent updates on kratom trends. To assess the current state of kratom-use initiation, sourcing, motivations, preference, conceptualizations, and perceived stigma, using survey responses from current and former users. Between April-May 2021 we recontacted 289 respondents who reported lifetime kratom use (on an unrelated survey) to answer kratom-specific questions. The sample (N=129) was majority female (51.9%) and white (71.9%). Most (69.0%) reported first trying kratom after 2015. Mean age of use initiation (29.9 years) was older than for other substances, including opioids. Kratom ranked as a preferred substance by 48.5%. The strongest drug association with past-year kratom use was vaped nicotine (3.31,95% CI 1.23-8.88). Use was less likely among those prescribed buprenorphine in the past year (0.03, CI 0.01-0.28). Past-month cannabis use (4.18,CI 1.80-9.72) had the strongest association with past-month kratom use. Over 40 use motivations were endorsed, many (but not all) supporting the "self-treatment" narrative of kratom use, including use as an opioid, alcohol, or stimulant substitute. Treatment shortfalls were associated with decisions to try kratom. Kratom use motivations are diversifying, with multiple factors driving use. As sales continue to increase, the public-health, clinical, and policy responses to kratom should be grounded in rigorous bench-to-bedside scientific research. Comprehensive study of kratom is currently lacking.