You could always put visine eye drops in his coffee on the last leg of a flight..and maybe he will get caught in a traffic jam on the way home from work and get a sudden bout of diarhoea.. (oh so naughty)
Not so much naughty - more, an incredibly stupid and criminal act. This suggestion turns up periodically as a means for Cabin Crew to punish those passengers or Pilots who in some way offend us. It is deeply depressing to think that any trained Cabin Crew member could stoop to poisoning (for that is what it is) anybody else, or that another trained crew member could promote this practise to a new-hire.
We often hear Cabin Crew complain that they would like both their employer, and the travelling public, to take them more seriously. Infantile behaviour is unlikely to change existing perceptions.