Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
These two issues could certainly be related. Any time a cat develops an allergy to fleas we tend to see hair loss and possibly skin sores on the thighs, heels/nocks and around the tail base and spine. So, before we worry about a larger dermatological problem, I recommend a serious attempt to clear the fleas.
Right now we are seeing a lot of resistance to flea products, especially in cats. Frontline and its knock-off fipronil-containing products do not work. In cats the top two products to consider are either Advantage II (could do Advantage Multi) or Revolution. The first mentioned Advantage product is not prescription. However, be careful and do NOT get the dog product which is toxic for cats. If you have any other furry pets (dogs, other cats, ferrets, rabbits, etc), they must also be treated for fleas with an effective product. AS well you must take care of the environment. That means vacuum every 3 days for 2 weeks. If you are worried the fleas are in the air vents, then call a professional terminator company to help. IF you have dogs who spend a lot of time outdoors, then treat the areas they spend time, especially if sandy (the best product is a sprinkle granule you can buy at most home improvement stores that is made by Bayer with the active ingredient of imidicloprid).
If Sadie has a lot of skin sores, then she may need an antibiotic +/- corticosteroid from her veterinarian to really get this to clear. Depends on the severity.
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