I suggest a book on tape, or whatever they are referred to now. You can put the earphones in, close your eyes and at least rest your eyes. I have a lot of trouble sleeping in the scrunched seat, so usually I do not sleep at all. With the recorded audiobook, at least my eyes were closed and I did drift off a few times. On other occasions, I would be so frustrated that I could not sleep, that I would be growly, and sat sitting staring at the tv. Not a good feeling to be angry at myself for not sleeping.
I have not used a medication, but I do use melatonin drops at home and will bring them on board with me. Another tip to feel better when you arrive is to stay hydrated. Drink lots of water, as the air in flight is so dry. I also drink a gatorade on the way to the airport, to get me started with good hydration. I might have a glass of wine with the meal, but as others have suggested, more alcohol is not smart. I bring healthy snacks and eat very little of the crappy meals on board.
I am a big believer in Rick's suggestion to stay in the daylight and walk about during the daytime. Although difficult, it does work to get me switched to the new timezone.
There are some websites that suggest changing your bedtime and waketime before your trip by an hour or so to be closer to your trip time; not sure that would work for me, as I usually work until the day before I leave, but it makes sense.
Have a great trip.