Cat with allergy

by Shannon
(Boston, MA)

cat rump

cat rump

cat eye clean day, cloudy eye also

cat eye clean day, cloudy eye also

under chin, clean day

under chin, clean day

cat rump
cat eye clean day, cloudy eye also
under chin, clean day


About 3 months ago, Baby moved to our house in Boston. A friend moved from Seattle to NYC and couldn't take his cat with him. She's a fantastic and laid back cat, but she appears to have several medical issues which seem to be defying diagnosis and treatment. We are hoping for some advice on sorting this out. By the way, she's 10 years old, and has been an indoor cat for the last 6 months. Before that, she was an indoor/outdoor cat.

So, the list: she has a cloudy eye that she's had since she was about two--more on this below. She also has a large patch (1" x 3") on her backside near her tail with no fur and small point-like scabs (perhaps miliary dermatitis?), and sparse fur in the spaces between each eye and ear, sometimes with the same small scabs. She itches at both areas. Importantly, she's had these sparse, itchy, scabby patches for most of her life. The vet in Seattle said it was food allergies, so Baby has been eating exclusively venison and pea (hypoallergenic) cat food for several years now, yet the patches and itchiness persist. Prednisone was also administered and provided some temporary relief. Lastly, Baby has black mucus/crusty "debris" around her lower lips and on her chin, and consistently oozes quite a bit of this black stuff (sebaceous fluid??) from the inside corners of her eyes. She has also had the lip/chin/eye issue for a long but indeterminate amount of time.

About 1 month ago, we took her to her first vet visit in Boston. This vet immediately identified the cloudy eye as the result of feline herpes--it seems odd that the Seattle vet didn't make any note of this in her records, but seems like a good diagnosis. The Boston vet also thought the bald patches were due to food allergies and recommended hypoallergenic food, despite the fact that Baby had been on this food for several years already and still had these skin issues. The Boston vet prescribed the very expensive d/d food and prednisone as a solution. We asked if Baby had feline acne since she came to us with the classic black mucus/crusties around her lips and on her chin. She said no, but gave no alternative diagnosis. She also checked for fleas, found none and consequently decided that a flea allergy wasn't likely.

My issues:
(1) I'm not satisfied with the food allergy diagnosis. After several years of eating hypoallergenic food, she still has the same itchy bald patches. Although our friend had been using Advantage to combat fleas (not sure how consistently), I'm wondering if Baby has a flea allergy instead, or perhaps something more exotic? I don't know much about flea allergies, but my understanding is that just a few bites a month can set sensitive cats off on a scratching frenzy that can lead to significant skin damage. Is there a way to distinguish between a flea allergy and a food allergy?
(2) I would like some suggestions about the lip/chin/eye secretions. Could feline herpes inflame these areas, or suppress her immunity, or cause overactive sebaceous glands? Is there any relationship between feline herpes and feline acne or similar presentations?

Any suggestions to sort out her medical issues/treatment would be great! Thank you.

Dear Shannon,

Thank you for writing in with your questions about Baby and for providing pictures to help me provide my opinion. I would like to try to help provide some relief for Baby.

First, I would like to address the bald areas in Baby’s hind quarters and in the area above her eyes and beneath the ears. This hair loss is consistent with a feline allergy. This is not the typical location of irritation caused by feline food allergies, but is the classic location for flea allergies. A feline food allergy mostly affects the muzzle and paws.

Additionally, if the hair loss was the result of a feline food allergy, Prednisone would not have provided even temporary relief for Baby. The fact that Prednisone helped, even slightly, is another argument for a cat flea allergy. Atopic allergies and flea allergies are treated with Prednisone.

Mixing a new hypoallergenic diet with a cat allergy medicine such as prednisone is not the best way to diagnose Baby for a couple of reasons. First, beginning a cat on a hypoallergenic food is not the proper regimen to diagnose a food allergy. And secondly, creating both changes at the same time will raise a question of which is creating improvement, if any. Since Prednisone would be used to treat environmental and flea allergies and the new D/d diet would be for a food allergy, if she shows signs of relief, it will be impossible to tell which change is helping.

Secondly, the bumps and mucus on Baby’s chin does sound like feline acne. However, it is difficult to see for certain from the picture, so without examining her or knowing why the veterinarian rejected that diagnosis, I can’t be certain. Feline acne can be caused by a plastic allergy (especially if Baby eats or drinks from plastic bowls) or poor or excessive grooming. Cat acne treatment requires daily scrubbing of the affected area.

Lastly, the eye concerns you have for her are definitely consistent with feline herpes. The cloudy eye looks like very old scarring to the cornea from the virus. The black discharge area in the corner of her eyes could be related to this same virus. The herpes virus could have created scar tissue in the tear duct, creating a blockage. Blocked tear ducts have no real health consequences.

The black discharge in the corner of her eyes could also be due to poor grooming habits. Perhaps Baby doesn’t groom herself well in that area, maybe because she’s busy grooming the areas of her skin where she is so itchy.

We certainly don’t know everything that feline herpes can cause, but from what I’m seeing in the pictures you submitted, Baby’s symptoms, aside from the cloudy eyes and eye discharge, are all symptoms of cat allergies, most likely to fleas.

The issue at hand now is how to get Baby accurately diagnosed and begin her cat allergy treatment. Treating a cat with allergy problems often requires some testing. I recommend bringing her to Angel Memorial in Boston. There, she can be examined by a dermatologist and begin testing for feline skin allergies. This testing will check for practically everything that could be causing her itchiness and hair loss, such as grasses, pollens, dust, mold, etc., including fleas. If she is, in fact, suffering from a flea allergy, treatment includes a once monthly dose of Frontline medication and Prednisolone to provide relief while the Frontline flea and tick medication takes effect. (To read more about my preference for Front line flea medication, please see Frontline Cat.)

In the highly unlikely event that a dermatologist finds nothing, a true food allergy test would be the next step. There are blood tests for pet food allergies, but they tend to be less accurate. Doing a true food allergy test involves feeding nothing but one protein at a time.

Thank you again for writing in with your questions. Please keep me posted on Baby’s progress. I wish you both the very best in your search to find your cat allergy relief!

Kindest regards,
Dr. Neely

Return to The Role of Cat Flea Medicine in Feline Allergies.