My small Yorkie gets severe car sickness. What can I give for trips?

Poor Rainbow! Unfortunately, by law it is illegal for the experts at Petco Pet Education Center, formerly Petcoach to recommend and give the dose information for any drug, including OTC drugs, without seeing the animal in person first. That's because doing so requires a veterinary client patient relationship which cannot be achieved via an internet forum. In addition, the experts cannot say for certain if a specific drug is safe for your dog. I would have her seen by a vet tomorrow to discuss the use of medication to help her with her car sickness. The vet can prescribe medication that is safe for her, including possibly OTC medications. You can do a few things in the car to help Rainbow as well. Keep her forward facing during the trip, and you can purchase a specially designed doggie seatbelt to keep her that way. They are available online or in pet stores. Keep the windows open a crack to give her fresh air. Limit food intake before going on the trip, and medications from the vet can help prevent nausea. Good luck on your trip!