Pink Cocaine / Tusi

"Pink cocaine" — also called tusi, tucibi, or tusibi — is not a single substance but a pink-dyed powder mixture sold under a borrowed name. Laboratory analysis of seized samples most often identifies a combination of ketamine and MDMA, sometimes with caffeine or other additives, and only rarely any 2C-B (the compound the name is loosely derived from). The pink dye is cosmetic and says nothing about the contents.

Because it is a variable mixture, tusi has no single mechanism of action; its effects come from whatever drugs a given batch actually contains. Where ketamine is present it acts mainly as an NMDA-receptor antagonist (a dissociative); where MDMA is present it increases release of serotonin and other monoamines. Two samples sold as the same thing can therefore behave very differently.

Reported effects depend entirely on the mixture and dose, and are inherently unpredictable. A batch weighted toward MDMA tends to feel stimulating; one weighted toward ketamine tends to feel sedating and dissociative. The core hazard is that the user cannot know which they are taking, or how much.

The central risk of tusi is the unknown: unknown ingredients and unknown doses make accidental overdose and dangerous drug combinations more likely. Combining a stimulant (MDMA) with a dissociative (ketamine), or either with alcohol, raises the load on the heart and the risk of overheating, dehydration, and loss of consciousness. Samples have also been found adulterated with other substances.