Green’s Dictionary of Slang

(US drugs) experiencing the effects of a drug, esp. heroin.

1938		D. Maurer ‘Lang. of the Und. Narcotic Addict’ Pt 2 in Lang. Und. (1981) 99/1: bending and bowing. See high [i.e. under the influence of drugs].
1942		Berrey & Van den Bark Amer. Thes. Sl.
1953		Anslinger & Tompkins Traffic In Narcotics 303: bending and bowing. Drug-exhilarated.