Why Dewormer for Dogs Is Oh-So-Important for Keeping Your Pup Healthy
When it comes to worms, it isn't a matter of if your dog will encounter these pernicious parasites, but when. Dogs can get worms from digging in dirt, mosquito bites, and even from their mom (both in the womb and through nursing). Factor in that it can be difficult to tell when your dog has worms and that some of these pests can also infect people, and it becomes all too clear why safe, effective deworming medicine for dogs is such an important part of caring for our furry friends.
But what perhaps isn't so obvious are the specifics, such as how dewormer for dogs actually works, which parasites it eliminates, and how often your pup needs to be dewormed. For these and other questions, we've enlisted the help of Alisa Hutchison, DVM, MPH, a professor of community medicine at the University of Missouri College of Veterinary Medicine in Columbia, Mo.
What Is Deworming for Dogs?
"Deworming" is the common term for using anthelmintic drugs to rid dogs of parasitic worms such as roundworms, hookworms, tapeworms, whipworms, and heartworms.
"Deworming medications vary in their mechanisms of action and which parasites they eliminate," Hutchison explains. "Some cause muscle spasms that paralyze the worm and allow the gastrointestinal tract to get rid of them. In this case, it's possible that some of these worms will still be alive and moving after they're out of the body. Another type of medication disrupts cell division and starves and subsequently kills the parasite."
Hutchison lists pyrantel pamoate, fenbendazole/febantel, praziquantel, ivermectin, selamectin, moxidectin, milbemycin, emodepside, and epsiprantel as common deworming medication used in veterinary medicine. Several of these are given orally, a couple are administered via injection, and a few are applied topically to the skin.
Dewormer for dogs is a regular part of veterinary care for several reasons:
- Parasitic worms are extremely prevalent in your pet's environment. Even if you take precautions (like promptly removing feces from your yard, keeping your dog from hunting small critters, and staying away from dog parks), it's impossible to avoid them completely. For example, a single mosquito bite can transmit heartworm, and swallowing a flea can lead to a tapeworm infection.
- While dogs can get very sick when infected with parasitic worms (especially puppies and those with compromised immune systems), they often don't show any signs of illness. This may sound like a positive, but because asymptomatic dogs can shed infective parasites in their poop, this can increase the number of worms in your pet's environment and put other animals at risk. So the longer a parasite is left unchecked, the more damage it can cause.
- Some intestinal parasites common in dogs are zoonotic, meaning they can infect humans. For instance, people who walk barefoot or work without gloves in soil or sand can come into contact with canine hookworms. These can tunnel their way into your skin and cause cutaneous larva migrans, an infection that produces itchy, raised lines on your body.
Deworming goes hand-in-hand with regular fecal exams, which are helpful in diagnosing several types of intestinal worms. How often your veterinarian asks you to bring in a fecal sample will depend on several factors, including local disease prevalence and your dog's lifestyle, but you should generally expect to provide a sample once or twice a year. Heartworm screening tests are a separate diagnostic tool and should be performed annually—even on dogs receiving year-round heartworm preventives.
How Often Should I Deworm My Dog?
If your dog is diagnosed with intestinal worms via their routine fecal exam or by other signs (like if you see something wiggling around in your dog's poop), your veterinarian will prescribe the best deworming medication for those specific worms. (Treatment for heartworms is typically more involved and costly, and dogs often need supportive therapies before they are healthy enough to receive medication to kill the parasites.)
But because parasitic worms are so ubiquitous, anthelmintic drugs should be given year-round as a preventive treatment. These are typically broad-spectrum dewormers that are effective against several types of pests.
How often your dog needs deworming medication depends on his age and other lifestyle factors, Hutchison says. To minimize the risk of parasitism in both pets and people, she bases her recommendations on the best practices set in place by the Centers for Disease Control and Prevention:
- Puppies can (and very often do) receive worms from their mothers. And with their immature immune systems, young dogs are particularly at risk of developing serious illness. Because of this, puppies should be given deworming medications starting at 2 weeks of age. They should then be dewormed every two weeks until they're at least 8 weeks old.
- Lactating mothers should follow the same deworming schedule as their puppies.
- All other dogs should be dewormed once a month.
If you're unsure whether your pet is receiving a monthly broad-spectrum dewormer, talk with your veterinarian. It's often included within your dog's heartworm medication.
Here's When to Take Your Dog to the Vet
Are There Natural Dog Dewormers?
There is no natural dewormer for dogs that matches the efficacy of traditional anthelmintic medications, Hutchison says. And though the word "natural" can imply safety, that isn't necessarily the case, she adds. Without regulation and rigorous testing, Hutchison says that some proposed natural solutions may even be toxic.
"The best practice is to use evidence-based and researched medications that are proven effective and safe for eliminating worms," she explains. "Most deworming medications are very safe and effective for the species for which they're recommended."
Do Dewormers Have Side Effects?
Hutchison says that deworming medications are generally considered to be quite safe (for pets—not worms) and that side effects are rare. However, some dogs can experience:
- Vomiting
- Diarrhea
- Lack of appetite
- Excess salivation
- Lethargy
- Seizure activity (this is very rare)
If you notice any changes in your pet after giving them deworming medication, don't hesitate to call your veterinary team. They can help you sort through what's normal and what isn't.
How Much Does Deworming a Dog Cost?
The cost of deworming medication varies by veterinary clinic, product, and your pet's weight. However, Hutchison offers the following estimates as a general guide of what to expect:
- Oral dewormer: $15–20 per dose for a medium-sized dog
- Topicals and injections: $15–35 per dose
- Heartworm prevention injection: $50–$350. The wide range is because some injections protect your pet for six months while others are effective for a full year.
