Can I Give My Dog Claritin?

Yes, with care
Loratadine is commonly referenced for dogs at published doses. The published veterinary reference range for loratadine in dogs is 0.2-0.5 mg per kg of body weight, given every 24h. In practice: 5 mg small dog / 10 mg large dog daily. Plain loratadine ONLY. Claritin-D (pseudoephedrine) is toxic.
Source: Veterinary Partner (VIN)
Get the exact range for your dog's weight

Skip it or ask a vet first if

Claritin-D / any -D decongestant version

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.

See also

Other antihistamine questions for dogs