(a nappy change between feeds might help him to wake up)
If mine is snoozy and I want to feed him those icy cold wipes and icy cold fingers do a marvellous job of waking him up *evil grin*

Had to do that a lot the week he was sick. All he did was eat and sleep.

Maybe try feeding him shorter feeds really often during the day, like an hour after his last feed and not let him fall asleep?

Drinking coffee is probably not a good suggestion