Mickey is a dangerous alcoholic drink. What did he contain?

ricin

chloral hydrate

methanol

cocainecapacitate them. Serving someone a Mickey is most commonly referred to as slipping someone a mickey.

Dear student 

In slang, a Mickey Finn (or simply a Mickey) is a drink laced with a psychoactive drug or incapacitating agent (especially chloral hydrate) given to someone without their knowledge, with intent to incapacitate them. Serving someone a "Mickey" is most commonly referred to as slipping someone a mickey.