Hartz ultraguard

I had bought this over the counter product at the Walmart. I used it on my pug and she developed a sore/burn where it was applied. I washed the liquid off with dish soap. My other dog was uneffected by the Hartz, however I have washed it off and we have gone with frontline plus. I am still waiting on my pugs wound to heal before I try frontline. I have been giving her dishsoap/vinegar baths in the interm. However, I am still worried how frontline will effect her.
I wish that this was more common knowledge abd pet owners do not have to find out the hard way. Also, I am lucky that Smushy did not suffer as much as some unlucky dogs.