The FDA pulled it from the market at one point because of a bad batch, but it's back now. It is not recommended for children. They may produce the same side effects as scopolamine. Ginger is the most famous. You can buy ginger capsules, or eat ginger snaps or candied ginger.
Ginger ale is okay, too, though it has very little ginger in it.
Large doses of raw ginger or peppermint oil can irritate the stomach lining as well as the mouth. In a car or ship, look at the horizon or other fixed distant point. The front seat is the best place for anybody prone to motion sickness. Eat light meals before and during travel, and avoid alcohol. In a plane, try to relax, and aim the air vent at your face.