Dear Dr. John,

My three-year-old cat has been suffering for a few weeks with patchy hair loss and red dots on her skin. I looked it up on Google and it says that she could have dermatitis.

She seems to be constantly itching, licking, and biting at herself and at times the skin gets red.

What could be causing this? She does not travel well and, as a result, she has not seen a vet since she was spayed when she was six months of age. I suspect she might also be due for shots. What should I do?

— A.U.

Dear A.U.,

Thanks for reaching out but the first thing I will say is that you need to get your cat seen by a veterinarian. Dr. Google is not the answer.

I do not know if your cat is strictly indoors or not but at this time of year, one of the first things that comes to mind is flea allergy or miliary dermatitis. Have you seen any fleas crawling on her skin?

Dermatitis simply means inflammation of the skin. When fleas bite, their saliva contains a protein which is released into the cat’s skin causing the cat to itch.

This can lead to exactly what you describe however, there are other possibilities which include ringworm, various mites, allergies to foods or other elements in the environment, bacterial infections, and even various autoimmune disorders.

Some of these conditions can also affect humans so make sure that nobody in the house is also itching or presenting with any kind of a rash.

There are medications that a veterinarian might prescribe to ease her travel stress.

A veterinarian will need to do a thorough physical examination and may need to pursue other diagnostic tests to rule out possible causes for her itching.

Appropriate treatment will then be given. Cat vaccines can be given good for three years, but the initial rabies vaccine is only good for one year and based on the timetable you presented, I suspect that she is overdue. Moreover, it is a legal requirement.

Going forward, you should probably have your cat seen annually by a veterinarian to maintain your cat’s optimal health. Good luck.

Dr. John de Jong is President of the World Veterinary Association. He owns and operates the Boston Mobile Veterinary Clinic and can be reached at 781-899-9994.