I am not sure whether my dog has worms. I often put garlic in its food but I don't know if that is enough to deter worms, and I am now considering buying worming tablets for dogs, for the first time since the little fellow was a puppy. I must admit that I am not too keen on the thought of feeding him poison to make him feel better. If I am going to give my little fellow something like that I want to make sure it can't harm him. What are the side effects of worming tablets for dogs?