Your dog is scratching, chewing at their paws, and rubbing their ears, and the pollen count explains why. Before you raid your own medicine cabinet, know this: some human allergy pills are safe for dogs, and some are not. According to a new guide from Whole Dog Journal, the three common over-the-counter antihistamines, diphenhydramine (Benadryl), loratadine (Claritin), and cetirizine (Zyrtec), are all considered safe for dogs when dosed correctly.
Here is what this means for your dog. Itching has more than one cause. Environmental allergies make dogs scratch and chew, but fleas produce the exact same signs, so check for those first before blaming the trees. If it really is a seasonal allergy, Benadryl is the usual starting point: about 1 milligram per pound of body weight, given roughly every 12 hours. A 50 pound dog gets 50 mg, usually two 25 mg tablets. Some dogs get sleepy on it, and the liquid form is easier to dose for small pups.

Two cautions matter more than the dose. Check the inactive ingredients for xylitol, sometimes listed as birch sugar. This sweetener appears in some human products and is extremely toxic to dogs. And because the right drug and the right amount depend on your dog’s size and health, ask your veterinarian before giving anything. Some dogs end up needing prescription strength allergy treatment, and no over-the-counter pill cures an allergy anyway. It is lifelong management, but for many dogs, a well chosen antihistamine takes the misery out of allergy season.
