An Update on the Epidemiology of Tusi ("Pink Cocaine").

Purpose of Review: Tusi, also known as "pink cocaine," has emerged across nightlife scenes in Latin America, Europe, Australia, and the United States (US). Tusi is typically a drug mixture containing ketamine and 3,4-methylenedioxymethamphetamine (MDMA). Due to tusi's inconsistent chemical makeup, surveillance and harm reduction efforts have proven difficult for researchers and consumers alike. This review synthesizes evidence from peer-reviewed literature, drug checking programs, toxicology reports, and law enforcement data published between 2020 and 2025 to characterize tusi's composition, epidemiology, and associated risks. Recent Findings: Drug checking services in various countries have identified ketamine and MDMA as the main components of tusi with additional substances often added (e.g., synthetic cathinones, cocaine, methamphetamine) in varying combinations. Laboratory data from Spain show that ketamine concentrations in tusi have increased over time. Surveys in Spain and Colombia highlight increases in initiation, polysubstance use involving tusi, and misclassification of its contents. Toxicology and case series reports indicate that harms associated with use stem largely from polysubstance mixtures rather than any single component, yet morbidity and mortality data typically focus on individual drugs detected. Summary: Tusi exemplifies a novel trend in emerging drugs: it is a blend of substances rather than a single compound, with its identity shaped by its distinctive color and association with nightlife. Its inconsistent composition and frequent co-use with stimulants and dissociatives elevate risk while complicating surveillance. Standardized survey items, expanded drug checking, and improved toxicological monitoring are needed to track and respond to this evolving mixture in the global drug supply.