When I was a child I suffered from motion sickness and since our family took montly car trips to visit relatives it was a pretty regular part of my life. This was before Dramamine, what helped me were lemon drops...yes, the old fashioned candy. For whatever reason I always got at least a little relief sucking on lemon drops. Nowadays, it might be something to try in addition to Dramamine.
Peppermints would work this way too - and settle the stomach. I always have my Altoids on hand.