I used to be that way as well. But half an Ambien, combined with melatonin taken properly cross-ocean to avoid jet-lag on arrival, works wonders. Ambien is prescription-only , but if you are traveling overseas you should be able to get it from your doc. The great thing about it is that it is short enough acting, and doesn't severely interfere with REM sleep, so if you take it near the start of a trans-Atlantic journey, when you arrive at your destination it will have pretty much worn off and you won't be groggy.