Green’s Dictionary of Slang

skee n.²

(drugs) opium.

1939		Howsley Argot: Dict. of Und. Sl.
1949		Monteleone Criminal Sl. (rev. edn).
1953		Anslinger & Tompkins Traffic In Narcotics 315: skee. opium.
2001		ONDCP Street Terms 19: Skee — Opium.

In compounds

skeed-up (adj.)

(US drugs) intoxicated by drugs.

1998

L. Stringer Grand Central Winter (1999) 53: I managed a few mumbled cautions to him against traipsing the streets skeed-up at this hour.