Health & WellbeingWhat's the difference between Advantage II for dogs and oral flea products?
[Advantage II](https://www.petco.com/shop/en/petcostore/brand/advantage?utm_source=PetCoach&utm_medium=questions&utm_campaign=bayeradvantage) flea prevention is applied to your dog topically, spreading over the skin and hair. It kills fleas through contact, which means that fleas don't have to bite your dog to be exposed to the preventive. On the other hand, with oral flea medications, fleas are killed only after biting your dog and ingesting the medication. One flea bite can lead to an allergic reaction in sensitive dogs. Additionally, some oral flea preventives last as long as 12 weeks. Pet parents may find this more convenient. Most topicals must be applied every 4 weeks. Regardless, either product must be applied or administered regularly and following label directions in order for it to be effective.
Updated on September 24th, 2025