My dog is itching so much that he has developed patches and redness. What are the causes and treatment?

Hi Danielle,

Thanks for sending your question to us.

Most veterinarians deal with itchy dogs daily – it is a very common problem! Itching can be very distressing to both the pet and their guardian. First, your vet will likely want to rule out any parasites such as fleas or mites, before considering other possible causes. They can identify any live fleas (if present – you don’t always see them on the dog!) or flea dirt (flea droppings). Even if there are no parasites found, your dog may be given medication since some parasites, such as the sarcoptic mange mite, can be very difficult to find.

The next thing to consider would be addressing any infections in the skin that could be contributing to the itching – either bacteria, yeast or other fungal infections. A simple skin swab and microscope analysis may be all that is needed to determine if these are present. Sometimes, a bacterial culture may be warranted as well to identify the causative agent and whether it is resistant to any antibiotics. This is especially important in dogs that have recurrent infections or skin lesions that do not respond to standard antibiotic therapy. Fungal cultures or molecular testing may be recommended if ringworm (a fungus- not a worm!) is suspected.

In addition, allergies should be considered in any itchy dog. Allergies can take on many forms – they can be environmental (to pollens, dust, etc.) or to substances in the pet’s food. Identifying the specific offending allergen is very challenging in dogs, and I typically recommend referral to a veterinary dermatologist if this is what the pet owner desires. Fortunately, it is not always necessary to identify the causative allergen to provide relief. There are several very effective treatments available through your veterinarian that can improve an itchy pet’s quality of life. The treatment selected will depend on your own pet’s medical history, severity and seasonality of clinical signs and of course, your budget. This may include, topical medication and shampoo, oral medication, supplements, injectable medication, and a diet change or diet trial.

Other causes of itching would include primary skin and hair diseases (for example, immune-mediated skin diseases) or skin cancers, but these are much less common than the disorders described above. I hope this gives you some insight. I would encourage you to discuss your dog’s itching with your vet, and they can help you figure out the best approach.

Good luck!

Dr. Hester