Internal parasites make your pooch sick, leading to health issues including vomiting, diarrhea, anemia, malnutrition and heart problems. Medications called anthelmintics, available through your vet, kill off pesky parasitic worms. After worming your dog, he might experience some side effects from the medication.
Your pup can catch intestinal worms from a variety of sources, including infected fleas or mosquitos, soil infested with the parasites' eggs and direct contact with another dog's feces, according to WebMD. Young pups can become infested with parasites in the womb or while nursing from an infected mother dog. Common intestinal worms include roundworms, hookworms, tapeworms and whipworms. Heartworms, unlike other internal parasites, infect your pup's heart. Some of these worms cause symptoms of illness; others don't. Your vet can physically examine your pooch for signs of worms and test his feces for their presence as well. If she finds them, she'll prescribe a medication designed to specifically target the type of worms your pup is suffering from.
The safest and most effective deworming medications, or wormers, come from your vet or can be obtained with her prescription for your pooch. Common anthelmintics include pyrantel pamoate, praziquantel, fenbendazole, ivermectin, milbemycin oxime and selamectin, according to the Doctors Foster and Smith website. Each of these medications target different types of internal parasites and some formulations include more than one to target a multitude of worms. Most are given orally in flavored tablets that you can feed to your dog directly or in a small amount of canned food. Others are injected; some, such as selametcin, which targets heartworms, are topically applied.
What to Expect
After you or your vet administers worming medications to your pup, he may experience vomiting, lack of appetite and gastrointestinal upset. While some medications dissolve the worms in his system, others paralyze them. As these paralyzed worms detach from your pup's internal tissues, you may find them in your dog's stool or vomit, advises Dr. Eric Barchas on his website. Usually side effects are minimal with wormers from intestinal parasites -- though a dog being treated for heartworms is at risk of suffering from a condition known as pulmonary thromboembolism. This potentially fatal condition occurs when the worms that are killed off by the anthelmintics cause a blockage of a pup's arteries, according to the American Heartworm Society.
Using Wormers Correctly
Follow the instructions for the medication your vet recommends -- many wormers require more than one dose to completely cure your pup of worms. If the dog misses doses, the worms will simply return. Always follow the dosage instructions your vet gives. Incorrect doses may be not only ineffective but also potentially harmful to your pup. Pregnant, nursing and ill pups can be at risk of some wormers, so consult your vet before using them. Never administer an over-the-counter broad-spectrum wormer to your dog without seeing your vet first, because such medications won't kill all types of worms.
By Susan Paretts
About the Author
Based in Las Vegas, Susan Paretts has been writing since 1998. She writes about many subjects including pets, crafts, television, shopping and going green. Her articles, short stories and reviews have appeared in "The Southern California Anthology" and on Epinions. Paretts holds a Master of Professional Writing from the University of Southern California.