I would call the number and ask a professional. Wouldn't that be most prudent?
There are a few different flea medications but you would need to consult with the Vet on the best one for your dog.
I highly recommend taking your fur baby in for an office visit and the vet can assist you. This veterinarian office is very reasonable.
Like mentioned, just call & ask. They have a sheet with all the medications & prices per weight range.
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