Dramamine and Bonine both work for me. I'm prone to motion sickness, but I like rollercoasters and such. To be honest, I don't know if a rollercoaster would make me sick because I always take dramamine. I did take Dramamine before going on Mission Space two years ago, and I didn't feel the spinning at all--I was fine. As for the drowsiness factor, Dramamine makes a "less drowsey" formula, but unless I'm already tired to begin with (like waking up at 3:00 am to make a 6:00 am flight) it doesn't make me tired. However, maybe it's just me. My friend uses those "seasick bands" when they go on a cruise, and she says those work for her and her kids.
I've given Bonine to my neice since it is chewable, and it prevented carsickness and she was fine after taking it, not tired or anything.