Green’s Dictionary of Slang

(US drugs) opium.

1937		B. Dai Opium Addiction in Chicago.
1938		D. Maurer ‘Argot of the Und. Narcotic Addict’ Pt 2 in AS XIII:3 191/1: skamas. Smoking opium.
1949		Monteleone Criminal Sl. (rev. edn).
1955		H. Braddy ‘Narcotic Argot Along the Mexican Border’ in AS XXX:2 89: The Hebrew skamas for drugs.
1959		J.E. Schmidt Narcotics Lingo and Lore.