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Updated on September 23rd, 2025
Pet's info: Dog | Mixed Breed Large (61lb +) | Male | neutered | 1 year old | 66 lbs
hi, i just gave my dog his flea medicine (vectra-3D) and right after i put it on his fur started getting black on his neck, now theres a big black spot and it smells really weird. ive used that flea medicine for months now and nothing like this ever happened, i tried calling my vet but there closed until friday. It looks like the spot is getting bigger and im not even sure if its from the medicine or if he rubbed on something. should i give him a bath? what should i do?
1 Answer

Answered By Kevin Sanada, DVM
Veterinarian
Published on November 22nd, 2017