Benadryl, the brand name of the generic antihistamine diphenhydramine, is not labeled for use in dogs but has remained a popular choice among veterinarians, dog groomers, and dog-owning families ...

Namely, diphenhydramine, or Benadryl, would be a potential option ... It may also be worth trying things as simple as not feeding your dog before a trip so they don’t have a meal or treats ...