Many new dog owners are surprised to learn that most young puppies already have worms by the time they are a few weeks old. They can become infected through drinking their mother’s milk, and from the environment. These pesky little worms can cause all sorts of problems for your pup, including an upset stomach, weight loss or even stunting their growth. That’s why it is important to worm your pup regularly. The thought of worms might make you feel queasy, but they are an inevitable part of your dog’s life, so it is important to know the signs that they can cause and how you can treat them. Some types of dog worms can even cause problems in humans, so deworming your pup is an important way to protect your family too.

In this article, we will take a closer look at deworming your puppy, giving you all the information you need to keep your pup worm free.

Common Symptoms of Worms in Puppies

There are some common signs that you can watch out for in your new furry friend, as they may be a symptom that your pup has worms:

  • Diarrhea
  • Vomiting
  • Pot-belly (swollen stomach)
  • Dull, dry coat
  • Weight loss
  • Weakness

If you notice your pup showing any of these signs you should visit your veterinarian. Ask your vet if you should collect a recent stool sample, as this can help to diagnose if worms are causing your pup’s problems.

How Often Does Your Puppy Need to be Dewormed?

Young animals are more susceptible to the effects of worms, as their immune systems are still developing and they have no immunity against them. A large number of intestinal worms can cause serious illness or even death in puppies. This is why young puppies need to be dewormed more frequently than adult dogs. Young puppies between 2-12 weeks of age should be wormed every 2 weeks, and then every month until they are 6 months old. Once puppies reach six months of age, they can follow an adult deworming protocol.

A General Deworming Guide for Puppies



Deworming Frequency

2-12 weeks

Every 2 weeks

3-6 months

Every month

>6 months

Every 1-3 months*

* An adult dog deworming protocol will vary depending on where you live, which worms your pup is at risk of catching, and if there are young children in your home (as they are at risk of becoming infected with some canine worms too). Talk to your veterinarian to decide a worming plan for your dog. Traditionally it was recommended that adult dogs should be treated at least four times a year, or every 3 months, for intestinal parasites. The AAHA now recommends monthly deworming year-round for the life of the dog. If your pup needs heartworm prevention treatment, then this can be started as young as 6-8 weeks and continue every month year-round.

Roundworms on Wood

Different Types of Worms

There are many different types of parasites that can infect your pup and cause him problems, and which ones your dog is at risk of depends on where you live. Here we will take a closer look at the most common types of worms that can infect dogs:


These are a very common type of worm to infect dogs. An infected mother dog can pass roundworms to her puppies before they are born or after birth they can pass through her milk. Pups can also become infected from eating roundworm eggs from the environment, from infected soil or poop.Major roundworm infection in puppies can cause symptoms like a pot-bellied appearance, diarrhea, vomiting, or weight loss. Sometimes the adult roundworms can be seen in a pup’s vomit or poop, they are a long, white spaghetti-like parasite. Humans can become infected with roundworms too, through contact with infected dogs, contaminated soil, or dog feces. These worms can cause eye, lung, heart problems in people, and children are at higher risk.


These pesky little worms can be transmitted from the mother to her puppies before they are born or afterwards through the mum’s milk. Dogs can also become infected if they eat larvae (young hookworms) from infected dirt or dog feces, or the larvae can attach to the dog’s coat and penetrate the skin.Hookworms are like mini vampires, as they attach to the lining of the intestines, and feed on your pup’s blood. This can cause some serious problems for your puppy and common signs include anemia (pale gums, weakness), poor appetite, and bloody diarrhea.


Pups become infected with tapeworms from fleas, mice, or other rodents. These are long, flat, segmented worms. Sometimes you might see tapeworm segments, which look like grains of rice, attached to your dog’s rear end or in his poop. A large tapeworm infection in puppies can cause them to have an increased appetite but with no weight gain, and to scoot their bottoms on the ground. Some types of tapeworms can cause serious disease in humans, but thankfully this is not very common.


Whipworms live in your puppy’s digestive tract and can cause chronic bowel inflammation. Dogs usually become infected from eating soil or dog poop infected with whipworm eggs. Severe whipworm infection in puppies can cause diarrhea with mucus or blood and weight loss.


Heartworms are common in dogs throughout the United States, and infection is spread by mosquitoes. Adult heartworms live in the dog’s heart and large blood vessels of the lungs, where they can cause a lot of damage. Common signs of heartworm infection in dogs include shortness of breath, weakness, and coughing, and if left untreated this infection can be fatal. Thankfully heartworm infection is totally preventable if you start your pup on heartworm prevention early.

Dogs that are older than 7 months will need to have a heartworm test, before starting any preventative medication. Most veterinarians recommend a yearly blood test to check your dog is free from heartworm infection.

To learn more check out our article Heartworm in Dogs: The Facts and How To Keep This Parasite Out.


Lungworm infection can be caused by several different types of roundworms. Some types of lungworm are transmitted via infected saliva or infected food and water, other types are transmitted by eating infected slugs, snails, or other small prey. The symptoms can vary depending on which type of lungworm is causing the infection, and the number and location of the parasites present. Symptoms can range from mildly increased breathing rate, coughing, sneezing or nose bleeds, to severe difficulty breathing and even death.

Puppy at The Veterinarian

Where Should You Buy Dewormers for Your Pup?

Pet shops, supermarkets, and pet websites often sell a variety of canine deworming treatments, but they aren’t always safe. It is best to get your worming treatment from your veterinarian. That way you know what you are getting is safe and effective – you don’t want to take any risks with your pooch! Did you know that some breeds of dogs are sensitive to some common deworming ingredients? Or that some types of deworming medication may not be safe for puppies? That’s why it is important to always consult a vet before using a new worming product.

Most people pick up worming treatments for their pup when they are visiting their vet clinic for their puppy’s vaccinations. Your veterinarian will be able to make sure your pup is healthy, accurately weigh your pup, and formulate a deworming plan especially for him.

Deworming Treatments for Your Puppy

Thankfully there are lots of different types of deworming products available for puppies, from easy dose liquids to tablets or even meaty flavored chews, so you are bound to find one that suits you and your pup. Deworming products differ depending on their ingredients and which types of worms they are targeting. Here are some common ingredients used in puppy dewormers:

  • Pyrantel (e.g. Nemex®, Drontal ®) is a common worm medication used to treat infections of roundworms, hookworms, and whipworms.
  • Fenbendazole (e.g. Panacur®, Safe-guard®) may be used to treat roundworms, hookworms, lungworms, whipworms, and certain types of tapeworms.
  • Praziquantel (e.g. Droncit®) is commonly used to treat tapeworm infections and is often used in combination with other antiparasitic medications.

Your veterinarian can discuss which products are safe for your pup, depending on the breed, age, weight, and which worms you want to target. Make sure that you read the box or leaflet carefully to make sure you are giving your pup the correct dose and that it is safe for use in puppies.

Usually, the dose is based on your pup’s weight, you shouldn’t guess his weight as this could mean your pup is getting too much or too little medication.

White Dog Laying on Lawn

What To Expect After Worming Your Puppy?

Usually, after you give your puppy a deworming product your pup will carry on as normal, and you won’t notice anything different.

However, sometimes if your pup has a high level of intestinal worms then he may pass some loose stools or even some dead worms in his feces. As gross as this sounds, it is much better that the worms have been targeted and eliminated.

If your pup is showing signs of sickness after receiving a worming treatment, then you should talk to a veterinarian for advice.

Can You Prevent Worm Infections?

Unfortunately, deworming treatments can’t stop your pup from coming in contact with worms and worm eggs, but they can get rid of any worms that are present in your pup’s body. That’s why you need to deworm your puppy regularly. There are some other measures you can take to decrease your pup’s chances of getting re-infected with worms:

  • Promptly pick up your pup’s poop
  • Don’t let your dog eat slugs, snails, mice or other small prey
  • Wash your hands thoroughly after handling your dog or their waste
  • Use effective flea control, as this helps prevent tapeworm infection


Puppies require frequent deworming treatments to keep them healthy, as certain worms can cause some serious consequences for your little pup. It’s important to continue with a regular deworming program for the rest of your dog’s life, as this not only helps protect your dog but is an important way to protect you and your family too. Your veterinarian can formulate an appropriate deworming plan for your pup and provide you with safe and effective veterinary products. That way you know your pup is receiving the very best care and you are helping to keep him happy, healthy, and worm free.


American Animal Hospital Association (AAHA). The 2019 AAHA Canine Life Stage Guidelines. Parasite Control. Retrieved May 14, 2020, from

The Companion Animal Parasite Council (CAPC). Dog Owner Guidelines. Retrieved 14 May, 2020, from