For those of us who have dogs suffering from car sickness due to anxiety here is something else to try.
This includes: Eyes to the Horizon Method. Making the car ride a pleasant experience. Sitting down in the car.
Starlit gets car sick. UGH. We like to go everywhere with the dogs. Even a 15 minute ride to the park put her into extreme anxiety and eventually she gets sick.
Our neigbors have cured many rescue dobermans with this method. It is working for us too. Take frequent small trips. Each trip for several weeks go somewhere with a reward. Their method was to go to McDonald's Drive Thru and get a plain cheeseburger, minus the bun. Then head back home.
We don't do McDonald's but I have placed the bag of her favorite cookies on the dash board. Her focus remains straight forward since she can't keep her eyes off the bag of treats. "The Eyes To The Horizon Method for Car Sickness"
Since our van is large Starlit tends to roam around and gets sea legs. We use treats to have her sit and stay in her seat. Then place the bag back on the dashboard.