Q: We adopted a male cat that has been itching himself raw and pulling out hair until he had bald spots. We gave him a cortisone shot and that helped and his hair is coming back but he is still overly sensitive and doing an awful lot of grooming and we still find hair clumps but not as much.
We ruled out fleas and this time of year (December) we are ruling out seasonal allergies. This cat was abandoned and lived in the woods for several months before we realized he was not just a wandering pet without a home.
We don’t smoke and our house is clean so we don’t think indoor allergies are the problem. We’ve had several cats before and none of them had allergies of any kind.
My hunch was that seeing this started a few months after we starting feeding him canned cat food with soy products in it. His symptoms started after that so we were wondering if maybe the soy messed up his thyroid and this is what could be causing the skin problems and itching. Could this be? We have taken him off any food with soy in it for a few weeks now and that and the cortisone shot seem to have largely helped. Could you tell us (my wife is frantic over this) how long a No Soy diet would have to be in place before we could figure out if soy was the culprit? Would adding a daily dilution (appropriate for his body weight) of Iosol Iodine to his food or milk help him regain proper thyroid function (if indeed that is the problem) or would it make hypothyroidism worse? He might have a few symptoms of that. If adding iodine isn’t a good idea then we can just wait longer to see if the No Soy diet will work but it would be nice to know how long to wait before trying something else.
A: There are many causes for itchiness (pruritus) in cats including allergies. The most common causes of allergies in cats are flea allergies, atopy (environmental allergens) and less commonly food allergies. Since fleas can still be present indoors during the winter and very sensitive cats can react severely to just a single bite, it is worth having your veterinarian evaluate your cat for evidence of fleas and sometimes to empirically treat. There are many environmental allergens that are non-seasonal and found indoors year-round so it is quite possible that your cat could have atopy. Lastly, he could have food hypersensitivity. The most common food allergens reported in cats are beef, dairy, fish, lamb and poultry, but an individual cat may be allergic to other ingredients or a combination of ingredients. The allergy is typically a reaction to the protein component of the ingredient. The most accurate way to test for a food allergy is to feed exclusively a special diet formulated specifically for this purpose for a period of time and to monitor response. These diets are available from your veterinarian. Since he received a cortisone shot to decrease itch, it’s not possible to determine if the diet change or the shot has made him less itchy. This does not sound like a thyroid problem and I would not recommend iodine supplementation. However, your veterinarian can check your cat’s thyroid level if you are concerned and help you determine the underlying cause of the itch so that he is feeling more comfortable.