What To Expect After Deworming A Dog

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As unpleasant as they are, intestinal parasites, such as worms, are pretty common in dogs. Dogs can get internal parasites in various ways. They often eat indiscriminately, such as eating an infected rodent, or they may eat uncooked meat that may have worm larvae. Puppies can even get certain parasites from their mother's milk. But one of the most common ways is by ingesting parasite eggs that are in contaminated soil. That dirt can be attached to objects that the dog eats or licks. A veterinarian is a great resource to guide pet parents on when and how a puppy or adult dog should be dewormed. Lern some generalities of what to expect after deworming a dog.


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Types of worms in dogs

Worms survive in their hosts by attaching to the intestinal wall and then taking the nutrients that the host consumes. There are four main types of intestinal worms that commonly affect dogs:


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  • Roundworms:‌ Puppies can get this parasite from their mother before they're even born. They can also contract them from their mother's milk. This parasite may also be picked up from eating contaminated dog poop and contaminated soil.
  • Tapeworms:‌ Dogs usually pick up tapeworms from infected fleas carrying tapeworm eggs.
  • Hookworms:‌ Dogs can get this from their mother's milk, their skin coming into contact with contaminated soil or sand, or ingesting contaminated soil.
  • Whipworms:‌ Dogs pick up this parasite from contaminated soil.


Worms should always be treated because if they are allowed to go on, they can seriously affect your puppy or adult dog's health by causing weight loss, digestive problems, or even anemia in severe cases. If you think your dog has symptoms of worms, contact your veterinarian.


What to expect after deworming a dog

If your dog is being treated for worms (versus a nonworm parasite), you may or may not see the adult worms in your dog's stool the next day. Hookworms are short and thin enough (like a hair) that you won't likely notice them. With tapeworms, you might see the ricelike worm segments. When a dewormer medication is given, it either kills or paralyzes the adult parasites living in your pet's intestines. That allows the paralyzed or dead worms to be passed from the dog's body. It's possible that your pet may have gastrointestinal upset during this process, such as vomiting or diarrhea.


If you are still seeing live worms a few weeks after deworming, let your veterinarian know. For some types of parasites, it's necessary to give medication more than once before every adult parasite is dead.

If you have more than one dog in your house, your veterinarian may have you deworm all the dogs unless the others are already on a monthly preventative. You should also make sure to keep your yard clean of dog stool, and it's a good idea to give your dog a bath the day after they've been dewormed to wash any parasite eggs off their hind end. However, if they're having diarrhea, also make sure to bathe them after that has stopped.



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Dog deworming medication

Deworming involves using oral medication that is either a powder that is sprinkled on food (like over-the-counter Panacur); a liquid, such as pyrantel pamoate; or tablets (chewable or nonchewable). Some products are by prescription only. If you know the type of worm your puppy has, you can choose a medication specific to that worm. However, if you choose incorrectly, you may find your puppy still has worms after deworming or, worse, that the medication isn't appropriate for the dog's age or causes unnecessary digestive upset. It's best to first consult with your veterinarian.


There are also "broad spectrum" dewormers, such as heartworm preventatives, that are effective against multiple types of intestinal worms. But again, this medication shouldn't be administered unless it's prescribed for your pet by a veterinarian.

Dog owners who have a new litter of puppies should talk with their veterinarian about a deworming schedule that starts when the pups are 2 to 3 weeks of age. Do not use a wormer on young puppies without first talking with your veterinarian because some are not safe to use until a certain age.


For weaned puppies and adult dogs, your veterinarian may ask for a stool sample in order to run a fecal parasite test to determine the correct medication needed. It's also good to note that not all parasitic infections are due to visible worms. There are microscopic parasites too, such as Giardia and coccidia. Also, dogs can have more than one type of parasite at a time.

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Deworming side effects in dogs

Medications that are commonly given to dogs are generally recognized as safe. However, adverse reactions are possible. Common side effects are:


  • Vomiting
  • Diarrhea
  • Bloody stool
  • Lack of appetite
  • Lethargy
  • Salivation

Less common side effects include muscle twitching, seizures, and allergic reactions, such as facial swelling or hives. Keep an eye out for these or other side effects so your dog can get treatment right away if they need it.

The bottom line

There are a variety of intestinal parasite infestations that dogs can get. The ones that are worms are roundworms, tapeworms, hookworms, and whipworms. Deworming treatment comes in powder, liquid, or tablet form. After being dewormed, you may or may not see worms in your dog's stool. Hookworms, for example, are so thin that they are hard to see. Treating parasites is often pretty straightforward; however, it's possible that while your dog is passing worms, they may develop side effects of deworming, like vomiting or diarrhea. Make sure to keep your yard free of dog feces to help reduce the chance of reinfection.


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