chase the dragon

Etymology
, a slang phrase of Cantonese origin from Hong Kong. "Chasing" refers to the careful movement of the liquid in order to keep it from coalescing into a single, unmanageable mass.

Verb

 * 1)  To inhale the vapour from heated morphine, heroin, oxycodone or opium that has been placed on a piece of foil.
 * 2)  To chase after the promise of a continually fulfilling high from an addictive substance.