Bumps on its Body, this is the typical closed abscesses.
Abcesses is known Problems. It is an old problem. The cats get somewhere on the belly “knobs”.
A bump under the skin. It’s not direct where they get injections
as if the GS wandered under the skin. Some cats really affected, and some doesn’t have.
The abscess was caused when the injection was made into the muscles near the leg and not into the subcutaneous space.
we always recommend: make a “tent” with your skin then inject the GS and keep the skin, the “tent” as long as possible 10 to 30 seconds then the GS can be better distributed.
Other solution :
Best would be to let it heal by avoiding scratching like using a jumper / something the cat can wear that covers losely over the sores. If medication is needed the best is a topical ointment like Betamethasone. It is greatly suggested to not use any medication that is orally administered as it means the cat needs to digest the medication and absorb it through the GI tract with is usually already overwhelmed when a cat has FIP and many suffer from diarrhea and then oral medication isn’t well absorbed at all.
Or you can use “Zeolith” :
Zeolite is a healing earth a claystone.
Taken orally, it can bind and drain pollutants in the body actually more famous and known in the context of “detox”.
Zeolite helps you to bind pollutants filtered by internal organs in the intestine and thus bring them out of the body, instead of reintroducing them into the metabolism via the intestine.