A dog that has been wormed has been given medicine to kill internal parasites, commonly called worms. The process is also called deworming and may need to be done regularly.
Worming usually refers to ridding dogs of intestinal parasites, although it can refer to eliminating heartworms, which is a much more serious condition. Dogs that have heartworms cannot be given a single dose of deworming medication. Instead, they require a careful multistage process to safely recover. Veterinarians recommend that all dogs be on a preventative heartworm medication, which also may help prevent intestinal parasites.
Intestinal parasites, such as roundworms and tapeworms, can eventually cause serious illness but are much easier to eliminate. The majority of the parasites can be killed with a single dose of medication administered either orally or in a shot. Some dogs may need a second dose later to be sure all the worms are eliminated. Although many deworming medications are available without a prescription, owners who think their dogs may have worms should take them to a veterinarian. The veterinarian can diagnose the type of worm and recommend an appropriate medication.
Dogs that have an unusual risk of picking up parasites may be put on a preventative worming schedule. Risk factors include dogs that scavenge in trash or live in areas with heavy parasite infestations.