Dear Welcome to HCM We understand your concerns I went through your details. I suggest you not to worry much. Your body has very little to do about the motion sickness. The culprit is the journey, winding roads. Getting yourself accustomed to these situations should make you perfect. Till then you can keep a stack of news paper (around 1 inch thickness) and sit on it while taking such journeys. They work as pacifiers. If you require more of my help in this aspect, Please post a direct question to me in this website. Make sure that you include every minute details possible. I shall prescribe the needed psychotherapy techniques which should help you cure your condition further. Hope this answers your query. Available for further clarifications. Good luck.