What causes motion sickness in dogs?
Motion sickness in dogs—as in humans—results from a disturbance in the body’s vestibular system, a complex set of structures and neural pathways located centrally in the inner ear that regulate balance and physical orientation. When there is a conflict between certain stimuli—what the eyes are seeing, for example, with what the body is feeling—the balance is disrupted and the vestibular system sends a distress signal to the brain, including its vomiting center.
“A driver almost never gets carsick because they’re looking out the window,” said Trisha Dowling, a professor of veterinary clinical pharmacology at the Western College of Veterinary Medicine in Saskatoon, Saskatchewan. “They’re focused on the outside and how the world is moving in relation to the car, and that helps. But a dog’s field of vision is limited to what the dog sees sitting in the car seat. At the same time, their body is feeling movement. There’s a dissonance that triggers it.”
Car sickness in dogs occurs most often in puppies because their inner ear structures are not yet fully developed. Many young dogs outgrow this. But some, like Raylan, never do. Additionally, dogs, regardless of age, can become anxious in cars, which can lead to motion sickness.
Can cats get sick too?
Yes. Cats also get anxious during car rides. This, in addition to vomiting, can result in urination, defecation and howling. “Cats live 99% of their lives in a house, so a car trip – a visit to the vet, for example – is extremely stressful,” Lechner said. “You’re dragging them out of their world.”
Cats, however, often travel in carriers. These contain vomit and other substances, which prevents the car seat from getting dirty. But you will still need to clean your cat and the carrier, which can be unpleasant for both you and your cat. (Small dogs can travel in carriers, too.)
How is motion sickness in pets treated?
Do not give your pet anything without consulting your veterinarian. Even over-the-counter medications can cause side effects. These recommendations should only be used as a guide for your conversations:
Maropitant citrate, brand name Cerenia, is the gold standard for treating motion sickness in dogs. It is a prescription pill for dogs with motion sickness that research has shown to be safe and effective. It was approved by the Food and Drug Administration in 2007 and a generic version became available last year.
Injectable Cerenia is licensed for dogs and cats, and is often used for chronic vomiting or nausea from surgery or chemotherapy. It can also be administered at a veterinarian’s office before a trip.
The tablets are not approved for cats, although veterinarians prescribe them “off-label.” Although Cerenia helps cats, other medications used in dogs generally don’t help, Lechner said.
Maropitant citrate works by blocking a neurotransmitter – or chemical messenger – called substance P, which is involved in nausea and vomiting, thus reducing the likelihood of them.
“Nothing will ever be as powerful as Cerenia,” Dowling said. “It’s the best thing we’ve got.”
Other options include human medications that can be used on dogs, although you should check with your veterinarian for dosage and other requirements:
- DimenhydrinateTrademarks Dramamine, Benadryl, Gravol, Travtabs, Driminate, Triptone. This is an antihistamine used to prevent motion sickness and may help dogs, especially dogs with vestibular disease. However, these can cause drowsiness.
- Meclizine hydrochloride. It is another antihistamine, and the active ingredient in the less drowsy version of Dramamine. Antihistamines target the balance center in the inner ear.
- OndansetronZofran brand. This medication helps prevent nausea and vomiting from chemotherapy, radiation, or surgery. It also works by blocking certain substances in the body involved in vomiting.
Talk to your veterinarian about what to give your cat. For example, your vet may prescribe an anti-anxiety medication to help ease your cat’s stress.
Most medications must be administered several hours before leaving. Follow the instructions on the label or your veterinarian. Some veterinarians recommend skipping food, but others suggest a small meal or snack. “Having some food in your stomach keeps things moving, so I think a small meal before heading out is better than going completely fast,” Lechner said.
Some people give their dogs ginger — since ginger is known to ease nausea — but there are no studies showing it helps, Lechner said. He added that other ingredients in ginger cookies and products, such as sugar substitutes, can be quite risky.
There are other steps you can take to help your pet:
- Keep the car cool. Dogs often pant when they feel sick, so air conditioning and ventilation can help. But don’t let your dog hang his head out the window. Flying debris can hurt sensitive eyes – and the dog may jump.
- Keep a dog in a crate or leashed in the back seat. This is the safest place for them, experts help.
What happens when Cerenia or other medications alone don’t work?
Talk to your vet about a combination approach. When individual medications failed to help Raylan, my vet suggested using Cerenia with the less drowsy version of Dramamine. The solution worked.
While Cerenia is generally effective, motion sickness in dogs is complicated with different pathways and mechanisms of action, which “explains why sometimes one medication isn’t enough,” said Kate Illing, a veterinarian and researcher at the Dog Aging Project. “Dogs have multiple receptors, neurotransmitters and nerves that affect nausea and vomiting. To treat, we try to target one or more of them.”
While Cerenia affects the vomiting center in the brain, antihistamines target the balance function of the inner ear, a strategy that ultimately proved effective for Raylan. “When Cerenia wasn’t enough, adding the antihistamine was the synergistic boost he needed,” Dowling said.
The bottom line: don’t give up. “It can be a confusing and often frustrating problem,” Illing said. “But persevere. And be patient.
