Is it safe to give a dog Tylenol?

The active ingredient in Tylenol, acetaminophen, is toxic to dogs and should never be given to them unless under supervision by a trained veterinarian. While Tylenol is a relatively safe and popular pain reliever for human beings, dogs differ radically in their ability to metabolize the drug.

Dogs can experience symptoms of liver toxicity after consuming seemingly small amounts of the drug; however, sometimes veterinarians prescribe very small doses of Tylenol to treat chronic pain in dogs. When Tylenol is given to dogs in a controlled manner, it is not harmful, but full-dose pills or gel caps designed for adult human consumption can cause liver damage, especially if a curious, unsupervised dog eats more than one dose.