Feline Acne


Feline Acne and similar conditions

Question: Hi Dr. Richards, My 13 year old cat has been diagnosed with cat acne. She's had it for over a month. Recently she became ill with a fever and general malaise (although eating habits and litter box were fine). After exhaustive tests including blood work, urine analysis and xrays, everything came up normal and the vet says it's a mystery. The doctor gave her Clovamax (antibiotic) drops and she became much better after three days. I have a few questions: Is it possible that one of the acne sores became infected, either by food or just hygiene, and thus caused her to have a bacterial infection? And second, the shampoo you recommend on your website, benzoyl peroxide, where can I buy that and is there a brand name? Is it safe to wash her chin with hydrogen peroxide or baby shampoo? Any other things you can suggest is appreciated. She's currently on an ointment the vet gave us. It works so-so. Thanks again for all the great advice you give us, Sincerely, Jeanne

Answer: Jeanne- There are several conditions that can resemble feline acne. These include Malassezia infection (yeast infection) of the chin, demodectic mange, deep bacterial follicle infections, usually with Staph bacteria or Pasteurella bacteria, ringworm (dermatophytosis) and immune mediated disease, especially eosinophilic granuloma complex. Several of these conditions are a little more likely in older cats, especially the bacterial and yeast infections which seem to take advantage of even minor decreases in immune system competency. Skin scrapings can sometimes reveal yeast infections or demodectic mange. Fungal cultures can rule out ringworm. Sometimes biopsy of the affected area is necessary to identify an underlying cause when acne is not responsive to therapy and simpler tests don't provide a diagnosis. When antibiotics are helpful it is recommended that they be used for 21 days since the area is favorable for bacterial growth and the infections can be relatively deep, making it take a little longer for a good effect. In Small Animal Dermatology, 6th Ed. (Scott et al.) the authors recommend using Espom salt soaks or compresses to help draw out infection. They recommend 2 tablespoonfuls of Epsom salt per quart of water and applying a very moist warm compress for 5 to 10 minutes. We haven't actually tried this very often because my clients tend to think their cat wouldn't tolerate it, but it is an option for enhancing the effect of antibiotics or other therapy. A number of topical medications have been advocated for feline acne but we have had the best luck with 2% mupirocin (Bactoderm Rx) applied twice a day and benzoyl peroxide shampoos (2.5% usually) which are marketed under several names, including Pyoben (tm) and Oxydex (tm). There are benzoyl peroxide gels made for people but concentrations over 5% are potentially irritating to cats so be careful using any of these. The best antibiotics for feline acne are probably amoxicillin/clavulonic acid (Clavamox Rx) and cephalosporins (Keflex Rx, Cefa-Tabs Rx). Fluoroquinolones like Baytril (Rx) or Zenoquin (Rx) are usually effective but I like to try not to use these antibiotics too frequently since we rely on them to be effective for life threatening infections. Some vets like erythromycin or clarithromycin but we have not tried these antibiotics. If there is an immune mediated component to the inflammation, or in rare instances when the inflammation gets so advanced that it is self supporting and must be controlled to allow antibiotics to penetrate the lesions, it can be helpful to use prednisone or other corticosteroids to aid in controlling the acne. Most of the time this isn't going to be necessary, though. Good luck with this. Since there was a good response to antibiotics it might be a good idea to ask your vet about using them for a longer time period to see if that would eliminate the problem. Mike Richards, DVM 2/12/04

Feline Acne or dermatophytosis (Ringworm) or demodecosis.

Question: Dear Dr. Mike: I am having a problem with my cats and what looks to be feline acne. I have been to two vets and a dermatology specialist. It started when I brought a stray cat into my home and kept her in a separate bedroom for one month until I found her a home. She had what I thought was flea dirt under her chin. Shortly after she left and my cats entered the room, they also came down with the black spots. Six months later and about $1000.,no one seems to know what is causing this. I also noticed what appeared to be flying gnats in the window of the room where the stray cat was. These were not in any other window in the house. The Dermatologist says this is only coincidence. She recommends continuing the lime dips even though it is causing one cat to scratch so bad that she is bleeding under the chin. This has been going on for six months. The one cat who appeared to be clearing up came down with another bad episode after the first lime dip. They all seem to be scratching more after the dip which is the most recent treatment attempted.

Facts: Ringworm test done Skin scrape Biopsy - showed that it was feline acne (is feline acne contagious & does it itch?)

Treatments to date: Nolvassan wash with Quadritop ointment Steroid ointment Steroid pills 2 week interval shots Bathing in 2 shampoos (demodex & sebolux) LymDyp with Humilac (seemed to make it much worse) Floucitonide cream (seemed to make a little better)

Cats: 3 related, 4 not Ages 3-17 They do not go outdoors One cat who is 17 is away from the others, she did not come down with the black spots All have shots & vaccinations and have been tested for Aids, lukemia, etc. I read the other cases on your website but it seems that I have already tried all the solutions possible. Can you please offer some assistance.

Thank you, Kimberly

Answer: Kimberly-

There are only two contagious diseases that complicate, or mimic, feline acne that I know of. They are ringworm (dermatophytosis) and demodecosis. Both of these are sometimes itchy conditions. Ringworm is found through culture of hairs (sometimes takes more than one attempt) around the affected area and demodecosis shows up in biopsy samples but it sometimes takes more than one sample to find it. We had a case in which it took three attempts to biopsy, taking two or three samples each time, to find the Demodex organisms in a group of infected cats. Some cats have eosinophilic granuloma complex that resembles feline acne but these are supposed to be distinguishable by examination of biopsy samples. Eosinophilic granuloma complex can be caused by allergies and flea bite hypersensitivity. If the new cat brought fleas with it, this might be a consideration.

Feline acne is usually treatable by topical treatment only. There are a number of things that people use for it, with benzoyl peroxide shampoos, vitamin A ointment (Retin-A, Rx), metronidazole gel and mupirocin ointment being the most common recommendations. When topical treatment alone is not sufficient, the use of systemic antibiotics or corticosteroids is sometimes necessary. Most cats will respond to corticosteroid treatment within a couple of weeks. Some vets have tried isotretinoin (Accutane Rx) in cats but according to "Muller and Kirk's Small Animal Dermatology, 6th ed" the success rate is only about 33% to this medication and it is pretty expensive.

If you have not contacted the dermatologist to report that treatment does not seem to have been successful, that would be a good thing to do. The dermatologist may suggest further testing, especially with the apparent contagiousness and the persistence of this problem or she may feel that it is reasonable to try some of the other treatments to see if they are more effective.

Demodecosis in cats is usually responsive to lime sulfur dips, at least according to the textbooks. Our clients do not like the product much, though. Alternatives are amitraz (Mitaban Rx) dips (we used 1/2 of the dog strength), selamectin (Revolution Rx) and ivermectin, although I do not know a dosage for this use in cats. Ruling out the possibility of demodecosis may be the reason the lime sulfur dips have been recommended but I can't say that for certain. It doesn't seem successful, so it may be reasonable to try another treatment at this time if this is something the dermatologist is concerned about.

Good luck with this. If you do not have success after talking to the dermatologist, or talking your vet into talking to the dermatologist for you (sometimes works better) it may be necessary to redo some of the testing. I know that is a bummer, especially with the costs involved and having already paid for the tests once, but it is sometimes the only way to find a diagnosis.

Mike Richards, DVM 1/26/2001

Feline Acne

Question: Dear Dr Mike:

My ginger and white male cat has minute black spots under his chin (his chin is white) Someone told me that these are like black heads. Is it possible?

Answer: Suzanne-

Cats get acne fairly frequently, so this is possible. However, yellow and light colored cats sometimes get pigmentary changes that are small black spots, so this is possible, too. Your vet can help you tell these conditions apart.

Mike Richards, DVM 12/28/2000

Feline Acne

Question: I am a subscriber to your service. My cat, Baxter, has an ongoing problem with feline acne on his chin. The first time it happened, my vet gave him a steroid shot which cleared the acne up in a day or two. However, it lowered Baxter's immune system and ear mites multiplied in his ears, causing an infection. And the acne returned in about a month. I have tried all the recommended remedies, benzoyl peroxide wash and ointment, regular peroxide, vinegar, warm compresses, but still the acne continues. What is causing him to have this problem and how do I treat it? He does seem to have a weakened immune system. How can I bolster that? Anne

Answer: Anne-

Unfortunately, I am not aware of a consistently effective approach to the problem of immune system deficiency problems, so I can't help with that portion of your question.

The current favorite topical treatment for feline acne among some veterinarians is 2% mupirocin (Bactroban Rx) ointment, used twice a day for three weeks. A published study on this treatment indicated excellent success in 60% of the cats treated, good success in 36% and one cat that developed an allergic reaction to the medication and had to be dropped from the study, making the failure rate 4%.

When feline acne does not respond to topical treatment, there are a couple of things to consider. The first one is whether or not it really is feline acne, or if it is one of the conditions that can mimic feline acne, such as ringworm, contact allergies, food allergies, yeast infections or demodectic mange.

If this is feline acne and topical treatment isn't working, the best approach is to culture one of the pustules and then choose an oral or systemic antibiotic based on the culture and sensitivity results. If this isn't successful, then it may be helpful to try isotretinoin (Accutane Rx). One of the recommended dosage schedules for this medication is 10mg per cat once a day, which is convenient because the medication comes in a 10mg capsule. An alternative is to continue to pursue the diagnostic process and consider a skin biopsy. This can be helpful in differentiating deep acne lesions (furunculosis) from other infectious/inflammatory conditions and that can help in determining the best treatment.

Hopefully, one of these things will help.

Mike Richards, DVM 11/6/2000

Feline Acne

Q: My cat has some kind of black stuff that almost looks like dirt under his chin. It's not from fleas, and I can't wash it off. Some days it's worse than others. Do you have any idea what this could be? I keep his food and water dishes clean. Thanks.

A: You cat probably has feline acne. It produces this sort of black debris in many instances and is usually confined to the chin.

Your vet can confirm this and make sure nothing else is wrong. Treatment may require antibiotics or corticosteroids but often it is possible to treat just by cleansing with benzoyl peroxide shampoo a couple of times a week.

There are a few cats in which this is a symptom of contact allergy to plastic food bowls. In that case, using a ceramic or stainless steel food bowl would be helpful.

Mike Richards, DVM

Last edited 10/31/04


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...