Can I Give My Dog Chlor-Trimeton?

Yes, with care
Chlorpheniramine is commonly referenced for dogs at published doses. The published veterinary reference range for chlorpheniramine in dogs is 0.2-0.4 mg per kg of body weight, given every 8-12h. Sedation common.
Source: Merck Veterinary Manual
Get the exact range for your dog's weight

Skip it or ask a vet first if

glaucomaurinary obstruction

The safe habit

Confirm any medication decision with your veterinarian, who knows your dog's health history and other medications. VetDose shows published reference data, not prescriptions.