Why is my cat suddenly aggressive, sensitive, and losing weight?

Gaining so much weight all of a sudden could be a sign of metabolic disease or an endocrine disease such as diabetes. She may feel ill and vulnerable and therefore tries to keep the other kitties away from her. Please take her to your vet ASAP for an exam and blood tests.

Hello. Laney's reaction to her kittens is pretty normal for a cat as they do not form very deep bonds with their offspring. However, the change in personality & weight loss is very concerning. There are multiple things that could be happening, from infectious to inflammatory conditions, so it is best to have her evaluated at your earliest convenience by your veterinarian. We need to rule out that there are no infectious conditions going on that could impact the kittens as well. I hope she is doing better soon & thanks for using Petco Pet Education Center, formerly Petcoach.

These sudden changes in temperament and the weight loss are commonly due to an endocrine problem called hyperthyroidism. The thyroid starts working more than normal increasing the metabolism (that is the cause of the weight loss) and causing behavioural changes similar to what you described. A clinical examination at your local veterinarian is essential to confirm this clinical suspicion and treat appropriately. A blood test and urine analysis are needed. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

I'm wondering if Portifoy is on aripiprazole or Abilify, and if this is causing adverse signs due to serotonin syndrome. I can't find any information on dosing in cats, but I would imagine that like most antidepressants hyperexcitability might be a symptom. Amitriptyline is another common medication that is used as an antidepressant in situations like this that can cause odd behavior. I'd recommend talking to your vet about whether or not you should continue the medications. While gabapentin can cause sedation I think it would be less likely to cause these symptoms.

Thank you for submitting your question regarding Skye. Gabapentin can cause some sedation and potentially appetite changes when first started. Mist of the time the effects wear off in several days. If her appetite does not return to normal soon, then I recommend contacting her veterinarian. I hope this information helps!

Thanks for using Petco Pet Education Center, formerly Petcoach! I'm sorry to hear Peaches is having issues. While there could be a behavioral component to her behavior, there can be underlying medical causes (pain, GI discomfort, an infection or illness, for example) that may be causing it as well. I would recommend she be evaluated by her regular veterinarian to determine the underlying cause for her behavior, have any necessary testing done (bloodwork, X-rays), and start any treatment (medical or behavioral) that may be needed. Good luck!

Gabapentin is a pain medication that can have various side effects in animal. Weight loss is not a very common side effect, but pain can cause animals to want to eat less. I would talk with your veterinarian and discuss this issue. It is possible that this medication is not fully effective for your dogs pain and so your dog is not wanting to eat. It is also possible that there is something else going on with your dog. Your vet should run bloodwork to ensure that there are no other issues going on with your pet that would cause the loss of appetite.