Hi Dr. B,

My dog has become very itchy the last few weeks. He is scratching himself all over, especially on his back. He is not losing hair, and his skin isn’t red or irritated. What causes this, and how can I help him?

Charlotte, Los Angeles

Your dog probably has allergies. Although people with allergies usually sneeze or suffer watery eyes and sinus congestion, in pets itching is the most common symptom. Cats may develop itching or scabs on the abdomen, the base of the tail, or around the neck and face. Dogs frequently become itchy on the tops of their feet, in their armpits and groin, and along their back.

Generally speaking, three things cause allergies in pets: fleas, pollen, and food.

Of the three, fleas are by far the worst offenders. In areas where fleas are endemic, the first step to help an itchy pet should always be flea control. Paradoxically, it is rare to find fleas on a pet who is allergic to them, because they will groom themselves until the fleas are gone. Yet just an occasional bite can be enough to cause severe irritation. Therefore, I recommend regularly applying Advantage or Frontline to all itchy pets if they live in flea country.

Pollen and food also cause allergies. Your veterinarian can recommend a variety of medicines, tests, and special diets to help address these allergies. I do not advocate trying to treat these types of allergies on your own.

As any hay fever sufferer can tell you, there is no cure for allergies. However, with proper intervention, most pets with allergies lead normal, comfortable lives.