Expert: Jessica - 8/30/2009

Question
QUESTION: Hello, I have a 2 year old male cat who's has all of a sudden become extremely aggressive and is spraying all the time. he will growl and bite many times. He is not neutered

ANSWER: Hi John.  Absolutely start with neutering.  I think that is going to solve at least 90% of your problem.  The spraying should stop once his testosterone is under control.  Very likely, it will help with his aggression issues, too.

However, I would advise an immediate vet visit.  Sudden aggression can be brought on by physical pain or illness.  Even though he may appear healthy outwardly, a vet can palpate all areas of his body and note your cat's response to their touch.  If a cat tenses up when the vet applies pressure to an area, this indicates pain.  The vet can also detect if any of his organs feel abnormally large or small or if the kitty has a fever.

If nothing is found to be physically wrong with him, schedule his neuter for ASAP.  If he needs to be on antibiotics, his neuter will probably need to wait until his infection is cured.  If it is found that he has abnormal organ function, special considerations will need to be taken before he undergoes anesthesia for his neuter.

After his neuter, there is still a lot of circulating testosterone for a few days, so it can take a short time before you notice an improvement in spraying behavior or aggression.  If you continue to have problems after a couple of weeks, I would recommend using a product called Feliway.  This addresses both spraying and aggression that are due to anxiety.  I use the plug in diffusers in my own home.  To learn more about how it works, visit www.feliway.com.  You can buy it online or at pet stores.  I have found it to be least expensive at amazon.com.  It's not a bad idea to start using this now if you don't mind the investment, since he is obviously feeling anxious about something.

If all else fails, you may want to discuss the possible use of a medication with the vet.  Clomicalm is one that is becoming increasingly popular for aggressive cats.  Although there are some cats who need treatment long-term, most cats need treatment only for a matter of months.  In some cases, former tom cats may respond to an injection of megestrol acetate.  This is a synthetic female hormone and is sort of an old school remedy to aggressive behavior in toms.  Most vets are reluctant to use it because it has the potential to cause diabetes and mammary tumors if used long-term.  But a single injection, if it becomes necessary, is unlikely to cause any such side effects.

Good luck!

Jessica



---------- FOLLOW-UP ----------

QUESTION: thank you so much for the detailed answer. I did forget to mention that he refuses to come home after he had a fight with another one of our cats. I have noticed that when he does come home (which is hardly ever) he will let you touch his head and neck but if you go any lower he will bite. we have also recently brought home a young female kitten. thank you very much.

Answer
Aahhhh, that puts a new spin on things.

First, I do think he should visit the vet right away.  To me it sounds very likely that he may have sustained an injury.  Perhaps it occurred in the fight, but maybe elsewhere.  It could have been due to a bite, or maybe he encountered something outside.  Potentially, he has an abscess somewhere from a bite wound that could have occurred during the fight with your kitty, or maybe something just struck a nerve.  Whatever the cause, it does sound like he’s in pain somewhere in his hind quarters for him to have this sudden aversion to touch anywhere past his head.  The vet can check him out for the cause and at least give him a pain reliever.

Secondly, some of the aggression could be coming from the pain, and some could be coming from the stress in the home.  The fight with your other kitty and this new kitten are both stressors that are probably weighing heavily on his mind.  The Feliway I mentioned should help a lot with that.  If your cats were indoor-only kitties, I would recommend to separate the two that had a fight and then reintroduce them slowly, but since yours go outdoors, that’s probably not going to help matters.

Definitely have your guy neutered right away.  We don’t need him sowing his wild oats out there!  And there is a very deadly disease, feline AIDS, that he is more likely to contract as a tom cat than as a neutered male.  It should also reduce the fights you’re seeing between your cats.

I hope the doctor finds out what’s causing his pain, and that the neuter calms down your household.  Best wishes!