Fenbendazole 222 is commonly used to treat intestinal worms in dogs and is generally considered safe when given at the correct dosage. In most cases, it does not directly affect a dog’s behavior.

However, you might notice small changes indirectly. For example, if your dog was uncomfortable due to parasites, they may become more active, playful, and relaxed after treatment. On the other hand, some dogs may show mild, temporary effects like slight tiredness, reduced appetite, or stomach upset, which could make them seem a bit different for a short time.

If you notice unusual or prolonged behavioral changes, it’s best to consult a veterinarian to rule out other causes.