We have to travel very long distances to see my family (usually a 14 - 15 hour drive). Our vet recommended Dramamine (sp). It's that motion sickness meds we take? It makes them sleepy. I'd call your vet to check how much to give. I think our 40lb APBT was allowed to take one pill for that period. It might have been one every so many hours. It's been a long time since we've made the drive with an animal. Good luck!