doob, n.² — Green’s Dictionary of Slang

doob n.²

also doub

[ety. unknown; originated with the UK Mods of the early 1960s and then spread among other users]

(UK drugs) amphetamine.

1969		I. Hebditch ‘Weekend’ unpub. thesis in Hewitt (2000) 133: Got any doubs (pills)?
2008		(con. 1960s) P. Brooker jackthatcatwasclean.blogspot.com July 🌐 ‘You’ve got to take some doobs if you go to the allnighters [...] ’ she said and discretely handed me 5 triangular shaped mauve coloured tablets from a packet in her hand bag.
2019		P. Baker Fabulosa 292/1: dubes, doobs, doobies 1. pills.