These findings add substantially to the knowledge base on kratom-associated deaths; these need systematic, accurate recording. Kratom’s safety profile remains only partially understood; toxic and fatal levels require quantification.

Typical case characteristics ( n = 156): male (80%), mean age 32.3 years, White (100%), drug abuse history (95%); reasons for use included self-medication, recreation, relaxation, bodybuilding, and avoiding positive drug tests. Mitragynine alone was identified/implicated in 23% of cases. Poly substance use was common (87%), typically controlled/recreational drugs, therapeutic drugs, and alcohol. Death cause(s) included toxic effects of kratom ± other substances; underlying health issues.

UK cases were identified from mortality registers by searching with the terms ‘kratom’, ‘mitragynine’, etc. Databases and online media were searched using these terms and ‘death’, ‘fatal*’, ‘overdose’, ‘poisoning’, etc. to identify additional cases; details were obtained from relevant officials. Case characteristics were extracted into an Excel spreadsheet, and analysed employing descriptive statistics and thematic analysis.

This study details the characteristics of such fatalities and provides a ‘state-of-the-art’ review.

Kratom ( Mitragyna speciosa Korth) use has increased in Western countries, with a rising number of associated deaths. There is growing debate about the involvement of kratom in these events.

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