Why does my dog get car sick, and how do I fix it?

What is actually going on

Puppies commonly outgrow physical car sickness by 12-18 months as the vestibular system matures. What often does not resolve is the conditioned anxiety, if every car trip has ended in vomiting or in a stressful destination (vet, groomer, boarding), the dog anticipates it and the stress response amplifies the nausea. Adult dogs presenting with new car sickness need a workup, ear disease, spinal problems, and hepatic disease can all contribute.

The desensitization protocol

1. Sessions 1-3: Feed the dog next to the parked car, then in the parked car with the engine off. No trip.
2. Sessions 4-6: Engine on, no motion, treats and calm exit after 2 minutes.
3. Sessions 7-10: Drive to the end of the driveway and back. Treat. Exit.
4. Sessions 11+: Progress to short drives ending at a fun destination (park, sniff walk), not the vet.

Gear and medications that actually help

A crash-tested crate or a Center for Pet Safety-rated harness restraint reduces motion (which reduces nausea) and prevents ejection in a crash. Face-forward positioning helps some dogs; a dark cover on the crate helps others. For persistent nausea, modern anti-nausea class medication used specifically for canine motion sickness is safe and highly effective; human meclizine and dimenhydrinate are used less often since the newer options became available. Never sedate the dog with over-the-counter human medications without vet guidance.