Definition of Chasing the dragon

Chasing the dragon: A practice of heroin use involving heating heroin and then inhaling it. Some heroin users have gone to this practice because they believe erroneously that it will protect them against contracting HIV and other diseases associated with injecting heroin.

"Chasing the dragon" carries a risk of untreatable brain damage with death occurring in about 20% of cases. Abnormalities occur in the cerebellum, the area of the brain that controls coordination of movement. Some patients develop symptoms of a rare brain disorder, progressive spongiform leukoencephalopathy in which fluid-filled spaces cover the brain's white matter and there is loss of coordination, slowed movements and difficulty moving and talking.