I would definitely use the lowest dose available, and you have a problem: most prescription sleepers work for 6-8 hours (definitely 8 for me, but I rarely use them)----so if you are going to use them, you want to be sure you take it about 8 hours before you are going to arise, or you may be very groggy.
There is quite a bit of variation in how people respond to these things. I'd definitely try it before your trip.
