Chasing the dragon

"Chasing the dragon" (traditional Chinese: 追龍; simplified Chinese: 追龙; pinyin: zhuī lóng; Jyutping: zeoi1 lung4) is a slang phrase of Cantonese origin from Hong Kong referring to inhaling the vapor from a heated solution of morphine, heroin, oxycodone, opium, or ya ba (a pill containing caffeine and methamphetamine). The "chasing" occurs as the user gingerly keeps the liquid moving in order to keep it from overheating and burning up too quickly, on a heat conducting material such as aluminium foil. The moving smoke is chased after with a tube through which the user inhales. The process may be referred to as a "foily" in Australian English.

In modern parlance the original meaning has morphed somewhat, and it has come to be used as a metaphor for an addict's constant pursuit of the feelings of their first high. The "dragon" being mythical represents a goal that can never be achieved, because it does not exist.

Such ingestion may pose less immediate danger to the user than injecting heroin, due to eliminating the risk of transmission of HIV, hepatitis, and other diseases through needle sharing, as well as the stress that injection puts on veins. A small puff can be inhaled as a method of gauging the strength of the heroin. Also, the lungs can act to filter out additional pollutants that otherwise would pass directly into the bloodstream; however, in any case, it is always harmful to expose the lungs to any kind of smoke and inhaling heroin itself may lead to toxic leukoencephalopathy.

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