Green’s Dictionary of Slang

drought n.

1. (drugs) a period when drugs are in very short supply or even non-existent.

[US]Current Sl. I:3 2/2: Drought, n. A time when the authorities make it difficult for addicts to obtain drugs.
[US]V.E. Smith Jones Men 166: It’s a drought or something. Ain’t nothin’ happenin’.
[UK]P. Baker Blood Posse 280: I don’t want the drought to reach me and can’t get any ganga.
[Aus]L. Davies Candy 12: There’s a drought. Or you could say a flash flood. A flash flood of no heroin.
[UK]K. Richards Life 406: When there was a heroin drought it was a bit rough.
67 ‘Dead Up’ [lyrics] Walk around with 5 zeds in my pouch / [...] / I smoke 1 cos it’s drought.

2. (orig. US campus) a period without sex or even dates.

[US]P. Munro Sl. U. 30: Steve hasn’t had a date in months — he’s in a serious drought.