Street ketamine use and differential risk of suicidality among adults in Taiwan.
Harm reduction journal September 29, 2025 Yen-Chun Kuo, Sheng-Chang Wang, Chuan-Yu Chen
Illicit ketamine use is strongly linked to increased suicidality, especially among recent users. In a study of 379 people in northern Taiwan, recent ketamine users had four times higher past-month suicidality (95% CI 1.35–12.27) and past users had 3.4 times higher risk (95% CI 1.01–11.45) compared with those who never used ketamine. The prevalence of middle to high suicide risk was 10.8% among recent users, 5.0% among past users, and lower among non-users. Excess risk appeared exclusively in suicidal ideation. Street ketamine users also had higher rates of major depressive disorder, disadvantaged socioeconomic status, legal issues, and lifetime suicide attempts (25%). Even past users remain at higher risk, underscoring the need for suicide risk assessments in community drug services.