Hello, We travel with two cats and for a while, they did pretty well not getting car sick. As they have aged, it is occurring more frequently, usually within the first twenty miles from home. ...
We use Cerenia (prescription medication) with Henry. There are other prescription medications along with some OTC medications and many can be formulated into "transdermals" so they can be applied to the ear rather than dealing with pilling a cat. There are calming natural products that i'm sure many will give their experiences.
Discuss the options with your vet, he/she has the best info about your cat and basic health information necessary to make the best choice.