Self-reported prevalence and severity of opioid and kratom (Mitragyna speciosa korth.) side effects

Ethnopharmacological relevance: Mitragyna speciosa (Korth.) is a traditional medicinal plant widely used in Southeast Asia for its opioid-like effects. Although kratom produces analgesia through binding of mitragynine and other alkaloids at the mu-opioid receptor (MOR), the association of long-term kratom use with adverse opioid-like effects remains unknown. Aim of the study: To determine the self-reported prevalence and severity of opioid-related adverse effects after kratom initiation in a cohort of illicit opioid users. Materials and methods: A total of 163 illicit opioid users with current kratom use history were recruited through convenience sampling from the northern states of Peninsular Malaysia. Face-to-face interviews were conducted using a semi-structured questionnaire. Results: Respondents were all males, majority Malays (94%, n = 154/163), with a mean age of 37.10 years (SD = 10.9). Most were single (65%, n = 106/163), had 11 years of education (52%, n = 85/163) and employed (88%, n = 144/163). Half reported using kratom for over > 6 years (50%, n = 81/163), and 41% consumed > 3 glasses of kratom daily (n = 67/163). Results from Chi-square analysis showed kratom initiation was associated with decreased prevalence of respiratory depression, constipation, physical pain, insomnia, depression, loss of appetite, craving, decreased sexual performance, weight loss and fatigue. Conclusions: Our findings indicate that kratom initiation (approximately 214.29 mg of mitragynine) was associated with significant decreases in the prevalence and severity of opioid adverse effects.