Zofran is great for nausea, but doesn't really help with motion sickness. It has a different mechanism of action. Phenergan works great for motion sickness but makes you drowsy. Dramamine and scopalamine work great for motion sickness but also make you want to sleep. When AF pilot trainees get motion sickness, we give them scopalamine patches, but they have to take an amphetamine (dextroamphetamine) to counteract the drowsiness. SO, all that said, just take one of the above meds and just realize that it is going to make you tired and pissy.
Good link: