How Often Should I Deworm My Dog?

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No one likes to think about parasites, but they are extremely common in dogs. In particular, intestinal parasites, which are commonly referred to as worms, are found in many puppies and adult dogs, and these parasites can be very problematic. Thankfully there are simple treatments to get rid of these pesky parasites and to help keep your dog healthy.

Intestinal Parasites in Dogs

There are many different types of intestinal parasites that are found in dogs. The most common kinds are:

  • Roundworms - These parasites are found in about one out of every 50 dogs tested with a higher prevalence in dogs that live in cooler places like Alaska, Wyoming, Indiana, West Virginia, Vermont, and Rhode Island. The worms that these eggs turn into look like spaghetti noodles and are especially common in puppies.
  • Hookworms - These parasites are also found in about 1 out of every 50 dogs tested and are especially common in warmer areas like West Virginia, Oklahoma, Louisiana, Mississippi, and Florida. The adult worms are difficult to see because they are only a few millimeters long.
  • Whipworms - While less common than some of the other worms, whipworms are still found in about 1 out of every 200 dogs tested. West Virginia, Kentucky, and Indiana have some of the highest rates of infection for this worm.
  • Giardia - This parasite may not develop into a worm but it still causes intestinal issues. It can only be seen with a microscope.
  • Tapeworms - These parasites are contracted by ingesting infected fleas. The worms will shed segments that look like pieces of rice on a dog's stool or around their rear end. They can cause rectal itching and weight loss.

How to Know if Your Dog Has Intestinal Parasites

The best way to tell if your dog has intestinal parasites is by having a microscopic fecal examinations done with your veterinarian on a regular basis. Heavy roundworm and tapeworm infestations may be obvious due to the presence of visible worms in your dog's poop. Many other parasites don't leave visual clues, so regular testing of the stool is warranted to prevent problems.

Deworming Options

If your dog has intestinal parasites, a dewormer will be needed to kill off the parasites. Dewormers can be topically applied, orally administered, or injected . There is no single dewormer that will kill all types of intestinal parasites. In order to treat intestinal parasites appropriately, your veterinarian will have to determine exactly what kind of intestinal parasite your dog has. Additionally, some dewormers are also recommended to be used monthly to prevent infections of some common intestinal parasites.

At-Home Treatments

Most pet owners are already treating their pets for the most common intestinal parasites with their monthly heartworm and flea medication. Many pet stores sell oral dewormers without a prescription in liquid, paste, granule, or tablet form to treat an active infection. These dewormers can contain the drugs fenbendazole, praziquantel, pyrantel pamoate, and/or febantel. Different drugs will kill different types of worms and some products contain a combination of two or even three different drugs. Most adult dogs on monthly preventatives will not need to use these medications. If you do use them, it is important to administer the appropriate amount of these products at the recommended frequency and route to your dog based on its weight. Additionally, you should always check with your veterinarian prior to giving any drug to your dog in case your specific dog has a sensitivity, allergy, or inability to process the drug based on its genetics or an underlying disease.

Veterinary Treatments

If your at-home treatments are unsuccessful or your dog has an intestinal parasite that cannot be treated with over the counter medications, a prescription dewormer will be needed. These may be administered orally, topically, or injectably and may need to be repeated depending on the type and severity of infection. Giardia is one type of intestinal parasite infection that can be difficult and lengthy to treat.

Frequency of Deworming

If you are trying to prevent your dog from getting intestinal parasites, a monthly preventative that includes a dewormer should be administered. But if your dog has an active infection, you will need to administer a dewormer at the specific dose and frequency that your veterinarian and the medication packaging recommends. This dose and frequency of deworming will depend on the type of intestinal parasite your dog has and the drug that needs to be used.

How to Prevent Intestinal Parasites

The best way to prevent your dog from being infected with intestinal parasites is to use a regular parasite preventative. These products are designed to prevent heartworms, kill fleas, and control several types of intestinal parasites on an ongoing basis. Additionally, don't allow your dog to eat another animal's feces or drink from stagnant water. Some people also avoid dog parks and public places that dogs frequently defecate to avoid ground that is harboring parasites.

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  1. Internal Parasites—Roundworm. Companion Animal Parasite Council.

  2. Internal Parasites—Hookworm. Companion Animal Parasite Council.

  3. Internal Parasites—Whipworm. Companion Animal Parasite Council.