Why is my cat's mouth swollen and red after removing a crust?

Thank for using Petco Pet Education Center, formerly Petcoach! It does sound like a small pustule with pus. If it was small and it is now drained and there is no inflammation present then it is probably fine to just keep an eye on her. If a discharge develops or it becomes warm to the touch or painful, have her evaluated by your veterinarian for further assessment and treatment as antibiotics are likely going to be needed. Good luck and have a good night!

Hi, thanks for using Petco Pet Education Center, formerly Petcoach! Poor Sage! Possible causes are: allergies, trauma from excessive grooming (rodent ulcer), allergic reaction, or from licking a caustic toxic substance. Without seeing a picture or examining Sage it is hard to tell you much more. Since cats can not tolerate human medications it is best to have Sage examined by a Vet today so she can be treated. I hope this helps and I wish you and Sage the very best!

Thanks for using Petco Pet Education Center, formerly Petcoach! This is very small. Possibly about 2-3mm in diameter. This may be the site of an infection or inflammation. It may resolve on its own. If it does not resolve in the next week or so, have him evaluated by a veterinarian for further assessment and treatment. Best of luck!

Hello. It looks like Firu has a particularly significant case of an eosinophilic ulcer. This may be related to some allergy in his environment. Your veterinarian can recommend some treatments that may help this to heal & hopefully slow down any reocurrances. Hopefully, he will be doing much better soon & thanks for contacting Petco Pet Education Center, formerly Petcoach.

I am sorry to hear that! I do think going to the vet would be a good idea. Cats can get many types of lumps at their mouths. From your description one thing I would want to rule out is eosinophilic plaques. These can be caused by allergies so getting on a low allergen food (I would recommend prescription due to cross-contamination at the manufacturing level) and medications can be vital! Of course it is hard to tell without looking at her so your vet may want to rule tests or take a biopsy first! I hope this helps!

Hello. This is a mild allergic reaction to something. It may take a few days to a week to go down, but if it does not, or seems to be getting larger, please see your veterinarian. Thanks for contacting Petco Pet Education Center, formerly Petcoach.

Thanks for using Petco Pet Education Center, formerly Petcoach! This can certainly be due to an infection at the site. There is a significant amount of inflammation as well which could have been from the trauma suffered during the fall. I highly recommend that you have him evaluated by a veterinarian for further assessment and treatment. They would be able to prescribe medications to help with this. Best of luck!