unusal cat aggression

Our female cat just attacked my husband for no reason.  Hissing, growling, and screaming - then attacking by biting and clawing violently.  She brought blood in several places on his arms and hands.  We had to lock her in the laundry room so that she would not try to attack anyone else in the home.  She is normally a gentle cat, quiet and stays to herself.  When she wants attention, then she will come to us for a rubbing session, crawling up on our chest for maximum attention.  So her behavior tonight is especially disturbing, as it is way out of the norm.  As we captured her, (had to cover her with a coat just to pick her up) we looked for any signs of physical problems, but did not see any.  There have been no changes in her diet, her litter box usage, or any other changes in the home.  She lives in the home with two of her offspring, with no problems.  We are very concerned...can you suggest any medical reason or disease for her behavior and what we can do?  Thanks, Kim

[PrettyKitty1]

Did you get her vaccinated and/or tested for rabies and toxoplasmosis? Both can cause drastic change in behavior, in which case, one of the symptoms is sudden aggression. The list below was provided to me and other members on the expert forum and it will give you an idea of what could be causing this. Please, take her to the vet.

Pseudorabies
CNS infection of many causes(viral, fungal, parasitic and insect, or spider bites that carry neurotoxin);
feline infectious peritonitis of the brain;
neoplasia in the brain;
severe head trauma
hepatic encephalopathy;
thiamine deficiency;
poisoning  (lead, mercury or other toxic heavy metal), organochloride compounds, benzoic acid strychnine and many others;
spongiform encephalopathy ("holes" in the brain that develop over time).

Spongiform encephalopathy, brain cancer, and other forms of encephalopathy can cause aberrant behavior.  There can be neurotoxin in spider bites.  Spider bites usually cause physical symptoms though, in addition to the neurological systems.

Let us know how she is doing.

[Ghilly]

Is she spayed?  If not, it's entirely possible that she has cystic ovaries.  Cystic ovaries will hormonally challenge a cat and cause their behavior to be very erratic from time to time.  Spaying will cure this.

Ghilly

[Mrs_Savas]

It does sound to me like it is likely a physical issue.  Both of the above answers are good.  It sounds to me like cystic ovaries or an exposure to a toxic substance.

So the first thing to do is to get her to a good vet as soon as possible.

However, if she gets a clean bill of health, you should consider if there has been any changes in her environment lately.  Sudden hostility is often a reaction to a radical change in environment like a move to a new place or a new person in the household.  Also, think if it is possible that someone has mistreated her, even unwittingly, while you are not at home.  Fear and confusion will very often cause cats to lash out when feeling uncertain or threatened.  Perhaps someone, a child or a person unfamiliar with cats, might have handled her roughly without meaning to be unkind?

If it does turn out to be an emotional issue arising from something like what I describe above, the only real treatment is patience and reassurance.  She will need to know that her home is safe and she is loved and it could take time until she is comfortable with this again.  Occaisionally a temporary mild, natural sedative like valerian is called for (I don't like stronger drugs for pets if avoidable).

Keep us posted.  Good luck.