what is the best treatment for cats that have been around a sarcopitic mange dog, the cat is getting spots .?

You really need to take it to a vet as soon as possible to make sure that is the problem.It could just be stress.I have seen this happen to mine when I moved and after he got used to his new environment it went away.
But if you can’t then most pet stores sell products that you can bathe it with

Good luck
and sorry to hear about this problem.

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