Review Of How Long For Tylenol To Work In Dogs References. The metabolism (mechanism for breaking down and removing drugs from. Under a vets care, tylenol (acetaminophen) can be used for fever and mild pain in dogs, but is fatal to cats and should never be given to them.

The metabolism (mechanism for breaking down and removing drugs from. If baby’s fever goes away for more than 24 hours and then comes back, or if. The active ingredient in tylenol pm, acetaminophen, is toxic to dogs and cats.