Hi there and thanks for your question.
There are a few things that can cause the symptoms you have mentioned.
Sometimes if a cat has had diarrhea the anus can be protruding slightly and red. If this is the case it will resolve on its own.
Your cat may have full anal glands. These are glands that sit on either side of the anus and can fill up with fluid. They usually need to be emptied by a vet. Usually cats with this problem will be seen scooting across the floor on their bum and this can cause a sore anus.
It is also possible that he has scraped it on something and it is irritated.
Most likely this is something that will go away on its own. It won't hurt to try a small amount of steroid cream or neosporin/polysporin.
But if it hasn't improved in 48 hours or so then a vet visit is a good idea.
The above is given for information only. Although I am a licensed veterinarian, I cannot legally prescribe medicines or diagnose your pet's condition without performing a physical exam. If you have concerns about your pet I would highly advise contacting your regular veterinarian.
Tony had a case of diarreha, he has not been rubbing on the floor, I put neosporin on it but he cries when I do. I have made him a Vet appt. How can I tell if his glands are full
If he had diarrhea, then this is likely the cause and your vet should be able to give you medicine to help with the inflammation. If he is sore when cream is put on then your vet may prescribe oral medication that should help.
Your vet will likely check his anal glands as well...it's not something I recommend for owners to do as it can be tricky, especially if his bum is sore.
I hope he does oK!
Thank you . I will try the cream again and see how it looks in the morning
God Bless You
Deb & Tony