Green’s Dictionary of Slang

shoot-up n.2

[shoot up v.2 ]

the act of injecting a drug; also attrib.

[US]H. Ellison ‘Gentleman Junkie’ in Gentleman Junkie 23: It had been a shoot-up session, no sex.
[US]Time 21 Dec. 20: The most dramatic technique is the ‘shoot-up’ where the more serious addicts inject themselves.