There are a variety of products on the market that claim to kill worms in dogs instantly. However, there is no one definitive answer as to which product is most effective. Some products may work better for certain types of worms than others, so it is important to speak with your veterinarian before choosing a treatment option. There are both oral and topical medications available, as well as natural remedies that can be used to kill worms in dogs. The best course of action will likely vary depending on the type of worm your dog has and the severity of the infestation.