West to East: You have to sleep on the flight, so consider a strong sleeping pill if you can't
Only time I would ever take a sleeping pill. But if you get 6-8h of solid sleep during the night flight it will make a HUGE difference. I personally can't sleep on airplanes (too cramped, strangers around me, etc) so this helps a lot. Have a little drink (1-2 small glasses of wine max) before sleeping to relax but not more - ideally you don't drink at all.