I should’ve done more research first.. But nevertheless I purchased Hartz flea medicine, the kind you put on their neck, and I did put it high up the back of my cat’s neck where she couldn’t easily get to it to lick it. My cat immediately started acting differently, crying like she was in pain, and she did manage to get a little bit in her mouth which caused immediate drooling and vomiting. I washed it off of her but too late, I should’ve never put it on her, because now she’s got problems. She vomited and drooled for days and thankfully that finally stopped. She’s got a completely different disposition about her, she cries out at random sometimes like she’s in pain, sometimes her cries are very bizarre sounding, and she’s got hair loss as well. This is terrible, they ruined my sweet little cat.