Chasing leaves is the term for the state you end up in, when high as a kite on Recreational Pharmecuticals. Its the point where you are completely at odds with what is happening around you, previously called 'tripping'.
Bob - "Are you ok there Gadd?"

Gadd - "Fuckin right mate, Im chasing Leaves here lad"
by Paul Gadd July 9, 2007
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