The roundworms spit out by the dog can be thrown into the toilet and flushed, and then the floor should be cleaned and disinfected. If a dog vomits roundworms, it means that there are already a large number of parasites in the body, and the body needs to be dewormed immediately. You can buy dog-specific deworming medicine for the dog to take, otherwise it may cause intestinal obstruction or perforation in the dog. This is normal. Dogs need internal deworming once every 1 to 3 months.