Suddenly violent towards other cat?

[twobananaz]

Out of the blue, isis has been attacking saki anytime saki gets close to me while isis is sitting on me. This has never happened before, and the only change is that they had a bath the other day with a new shampoo? Is a trip to the vet in our horizons?

 

[catwithmycoffee]

A bath takes away familiar scents, and can make cats think that their long time housemate is an unfamiliar feline.  When my cat Sam came home from the groomer (which included a bath), his sister Lizzie kept hissing at him and running away for a couple of days afterwards. 

If the 'attacks' by the one cat are very aggressive, you may want to try separating them and going through an introduction phase to get them used to one another again.  Really don't know what else to suggest with so little information.  Did you do the bath? Did they go to a groomer? What kind of shampoo did you use? How did they act towards one another before?
 

 

[twobananaz]

I have had to separate the aggressive one, by putting her in my bedroom, which was her safe room back when we first adopted her. I gave them the baths myself at home, using the same shampoos on each cat. They have never been cuddly, but they would at least play fight or give each other occassional licks on the head. They were both adopted as adults, separately, each at about a year old. It seems like the aggressive one only growls and lunges at the other when the aggressive one is sitting on my lap and sees the other coming too close to us. It used to be she wouldn't like it much, but would just ignore her, but now she tries to attack. If this continues for much longer (over the weekend) then I will get some feliway and do a reintroduction I think