Q: With the cold weather approaching my dog has been scratching all over. His skin is covered with tiny white flecks, somewhat like human dandruff but with a round look. He is biting his nails and pulling at the hair on his chest.
A: The most common cause of itchiness in dogs is allergies. Dogs can have allergies to things in the environment such as trees, grass, weed pollens, house dust mites and molds. During the winter months house dust mites and molds are the more common causes of allergic symptoms. The low humidity during the winter can lead to dry skin which can make the itching worse. Food allergies can cause the same symptoms as environmental allergies and are more common in younger dogs. Dogs with food allergies will itch all year around. Some environmental allergies may be limited to certain seasons of the year.
To diagnose food allergies, the dog must be fed a limited ingredient or hydrolyzed diet for 8-12 weeks. There are prescription diets that have been developed for dogs with food allergies. You must not feed any other food, treats, flavored vitamins or medications during the food trial. If the dog fails to improve on the food trial, the next step is allergy testing and allergen-specific immunotherapy (allergy shots).
Other useful treatments include antihistamines, medicated baths and leave-on conditioners, and omega 3 fatty acids. I would suggest seeing a veterinary dermatologist to evaluate your dog’s condition and suggest a customized treatment plan. While allergies are the most common cause of itching, other conditions such as seborrhea can cause generalized scaling and itching.