I have cured two dogs using ginger snaps. First, buy cookies that have real ginger in the ingredients. Next, make sure your dog likes ginger snaps. If so, start short trips around town and slowly feed your dog pieces of cookies. I gradually extended the outings and the cookie feeding until we were safely taking two hour trips in the car. After mine seemed to be cured, I weaned them off of the cookies. Before the ginger snap remedy, both dogs (one was a pup and the other a 6 month old rescue) ran and hid any time they thought they were going to be subjected to a car ride. The cookies had the added benefit of making them want to go for rides because rides = cookies.