I wonder if it's an allergy, possibly even seasonal. My thought would be, since the bath helped so much, to get some waterless bath products for pets like the foam or cleansing wipes for sensitive skin. This would allow you to clean it daily (or every other day to avoid drying out the skin) while avoiding the stress of a full bath.
I hope you find something that helps!
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Brandi Washburn
Executive Director
Bigglesworth Sanctuary
VA
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