I don't think I've ever changed sleeping habits a week prior to a Europe trip. Nor have I taken three days to get there.

I've flown TATL Y dozens of times. It sucks, but you just do it and survive. Aisle seat at least provides room for 1 shoulder and (when the carts aren't there) 1 knee. Get up a walk a bit. If you fall asleep for an hour or two, consider yourself lucky. If you don't, no biggie. I wouldn't advise messing with drugs unless you know exactly what they do to you. I'm always wired enough to power through most of the next day, maybe grab a nap at the hotel if I need it, and crash a little early the first night in the hotel.

Sometimes having a couple predeparture cocktails at the airport bar helps make me drowsy enough to doze for part of the flight. But I wouldn't recommend getting hammered - you'll just wake up dehydrated, not well rested, and with a nasty hangover. If you're going to drink, make sure you two-fist with a bottle of water.