I'm not sure if it's a direct potentiation or some sort of synergy of effects, however, I have found recreational doses or armodafinil (600-750mg) cause opiates (well so far I've only tried codeine) to be significantly stronger. Like I'm talking, I can eat 40mg of codeine and it literally feels like I've eaten ~30mg oxy and have a huge energy buzz on top of it. As a side note I don't use opiates very often and would have little or no tolerance. The difference is just massive; even if I'm on a study dose 150-300mg, and only eat 20mg codeine,, I'll end up with a really nice subtle warmth high alongside the energy and focus from armodafinil, like equivalent to ~100mg codeine.
I'm not sure what the actual interaction is here though so I haven't been game to try the stronger stuff I have (oxy and tramadol) in case something bad happens. Anyone know anything about this interaction/potentiation?