The first thing to realise when dealing with car sickness is that in 95% of cases it is stress related and not motion related. The most powerful memory imprint of any dogs brain is probably the car ride when it was taken away from all it ever new to be safe and secure, its litter mates and its mother. The most traumatic memory a young dog has is in relation to a ride in a car. So its not surprising that subsequent rides in a car should evoke very strong mental and subsequent physical trauma.
The solution is very simple. If the dog has been sick in a car then estimate how long it was in the car before it was sick, say 20 minutes? Find a park about 5-10 minutes from home, preferably one just around the corner, even one within walking distance that the dog has been to before…. but this time drive there. Ideally have someone else in the car too, to soothe the dog and distract him from the ride. Keep him happy all the way to the park. When at the park do all the enjoyable things that the dog loves, fetch the ball, chase the Frisbee, frolic with dad etc. The stay at the park doesn’t need to be that long…. just as enjoyable as possible. Then drive the dog home soothing him all the way again and when home make just as much fuss of the dog as you did at the park. Finish the session with his meal or a treat if time and conditions permit.
This exercise is repeated several times a day or daily if time is limited. Once the dog is enthusiastic to go in the car then the length of the trip is lengthened slightly to 10-15 minutes etc. Once you can drive with the dog for 30 minutes with no signs of stress or anxiety then you have the problem pretty much licked. Some dogs may take a little longer than others. The idea is for as many happy repetitions as possible to overwrite the initial mental imprint the dog has from its youth (or whatever other event caused the initial trauma).
I have had a (client’s) dog that suffered from chronic carsickness totally ‘cured’ (if that is the right term) in 3 days. That was with five car trips per day over the three-day period. The owners were impressed (even if I say so myself) and I am still getting referrals from them as a result.
This method has always worked, but I have heard of one dog that was sick due to some kind of balance problems and this method didn’t work for it. A trip to the vet after the method failed brought the problem to the surface. But if it only works for 95% of the dogs it’s used on then I think it’s quite successful!