Loratadine is safe for dogs, but only if you use it under the prescription of your vet. It is mainly prescribed to manage allergic reactions, particularly one that involves airway obstruction. The drug generally has minimal side effects.
Loratadine is safe for dogs weighing over 30kg at a dosage of 10 mg daily. For smaller dogs see a veterinarian for dosage. Also only give your dog this medication for 7-10 days and if symptoms persist go and see a vet