I applied Advantix to my Yorkie puppy for the first time a few days ago. My understanding is that it's absorbed through the skin anyways--that's why it lasts for a month. I didn't brush her before I applied--I just separated the hair the best I could with my fingers and squeezed the applicator onto the exposed skin. No problems at all. She was drowsy for a few hours afterwards, but I think that's normal, and she perked up and acted normally after that.
If she didn't have an adverse reaction after you applied it to her roughed-up skin, I'm sure she'll be okay, but next time, be more gentle
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