My cat had a ? skin disorder and had allergies to which didn’t happen until lying on the closed in screened in porch. She NEVER had fleas and was treated JIC,
I have a cat who also has a white under- neck. Never see a flea but when I comb her.. she has them. I also have a cat who is allergic to fleas and if I don't keep the flea meds on him he has seizures. I HIGHLY recommend this vet. He is caring and knows his business, and his employees are also caring and very helpful.
They are awesome but it does sound like your cat is allergic to fleas.My cat is and even if she only has one flea on her she gets scabs but it is definitely best to call them they are absolutely wonderful.
I'm not a vet, I'd call them directly.
Call them they are extremely kind and helpful
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