A. If your dog is itching because of fleas infestation (so if you still can find fleas on him/her) you should wash his/her bedding and spray your house with anti-flea spray. You should not repeat Fipronil treatment.
If he/she doesn't have fleas anymore but is still itching a lot then it could be due to flea bite allergy. In this case you should take your dog to your vets to confirm diagnosis and to get treatment
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