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You are not the only person who hates seeing parasites on your beloved pet!

However, the worms living inside our pets, which we cannot see, are as dangerous as those that feed on them from the outside. 

As a loving pet owner, you want your pet to be worm-free. You want them to develop without a parasitic burden on their bodies, so you worm them very often.

Is there a way to tell when it’s time to worm your pet without wasting money on worming medications? 

In this article, you’ll learn to identify the signs of worm overpopulation, the right worming schedule for your pet, and how to prevent reinfection after treating your pet for worms. 

Before we get to that, let’s first look at the type of worms that can infect your pets.

What type of worms are we talking about? 

Dogs and cats can get infected with 6 different types of worms. However, not all of them are very common or picked up easily.


Roundworms are one of the most common intestinal worms in dogs and cats. They are long (roughly four inches) noodle-like worms that lodge in the intestine. Unlike most other worms, such as hookworms, they don’t feed off of the animal’s blood, instead, they feed on partially digested food. 

Roundworms are more threatening to puppies and kitties. That’s because they directly compete with them for food, which burdens their system and may result in stunted growth.


Hookworms are a nasty type of small intestinal worm that’s common in many countries throughout the world. These small worms live in the intestine where they get their meals by attaching and sucking blood from the walls of the intestine. The damage they cause can be mild or life-threatening depending on the severity of the infestation.  


Tapeworms are flat, long, and white worms with tape-like segments and hook-like mouths. They attach themselves to the walls of the intestine and feed off of digested nutrients in your pet’s blood. 

The species of tapeworm that’s common to both cats and dogs is known as Dylidium caninum. This type of worm is mainly spread by fleas. Infestation occurs when a flea carrying tapeworm larvae is ingested by your pet (usually happens when they’re grooming itchy spots). This is one reason why you need to treat stubborn flea infestation with the best flea treatment products available.


Whipworms are small parasites that live in the large intestines of dogs and cats. While they’re more common in dogs, cats are susceptible to the parasite too. Like hookworms, they have a hook-like mouth that attaches to the walls of the intestine to enable sucking. In large numbers, the continuous biting and piercing of intestinal blood vessels can cause inflammation and bloody diarrhea. 


Though lungworm infection is less common than all the previous worms, this is a parasite that many owners fear. That’s because the damage they cause can take weeks, if not months to heal completely. And, in some cases can be fatal if untreated or poorly managed after treatment.  

The larvae live in the lungs and obstruct the airways. This can lead to poor oxygen absorption, fluid buildup in the lungs, weight loss, coughing, and pneumonia.  


Heartworms are another parasite that affects cats and dogs. They are very dangerous because, well, they’re lodged in the blood vessels of the heart and lungs. These worms can grow a foot long and without detection until they’re causing serious damage to these organs. 

Now, these worms all seem scary, but… how do cats and dogs get them in the first place?  

How do dogs and cats get worms? 


dogs and cats get worms through fleas
Photo by CDC on Unsplash

As if biting your pets and causing skin irritation is not enough, fleas can also transmit tapeworm larva. This usually happens when your pet unknowingly ingests fleas carrying tapeworm larvae while grooming his/her coat. If you’re still struggling with a flea infestation, then here’s what you have to do to get rid of fleas before they become a serious problem. 

Contaminated soil.

Infected birds, sheep, cattle, dogs, cats, ferrets, and other critters shed worm eggs back into the environment through their feces.  If these feces are exposed, which they most times are, worm eggs can lay dormant in the soil for long.

BTW, those are earthworms in the image! 

What this means is that by simply stepping out into the sand, your cat or dog can pick up these eggs on their body. Especially roundworm eggs which are particularly sticky. They can get caught on your pet’s coat, noses, or paws, where they’re then ingested during grooming.  

Dog owners clean their dog’s paws after a long walk, especially on unpaved roads and during the wet season. Washing is the best, and this pet paw cleaner makes the job much easier.

Scavenging or eating infected meat.

dogs and cats get worms through scavenging or eating infected meat
dogs and cats can get worms through scavenging or eating infected meat

Coming from the previous point, you know that many other mammals are host to different parasitic worms. 

Humans, dogs, and cats can become infected when they eat infected hosts, for instance, goats, cattle, and sheep. This can be through eating poorly cooked meat or offal (liver, lungs, and kidneys). Or when they (dogs, but mostly cats) catch and consume prey that’s a host to these worms. That’s why you need to stop your dog from eating random junk he found outside. You don’t know what’s on them!

During pregnancy and/or during nursing.

puppies and kitties can get worms during breastfeeding
Image by Franz W. from Pixabay 

Some worms don’t just sit in the animal’s gut waiting for the right time to develop into adults. Many worm larvae invade the muscle and other organs where they form harmless, dormant cysts. They can stay in the cysts for years. 

Pregnant or nursing animals going through immune-compromising physical changes can pass these cysts to their offspring during birth or breastfeeding. And since young animals have developing immune systems and digestive systems, it’s important to start deworming ASAP. 


Mosquitoes don’t just transmit malaria or zika virus to humans, they can transmit heartworms to dogs too! Mosquitoes carry the worm’s offspring from one dog or cat to another where they develop undetected. 

“…are humans also at risk?”


Humans are not the preferred host for heartworms, so verrrrry rarely would a human catch heartworm from a mosquito bite. Here’s a helpful page that answers a lot of questions regarding heartworms.   

We’ve seen how easy it is for your pet to pick up some of these worms – or come loaded with them. How can you tell if your dog or cat has worms? Are there any noticeable signs?

How do you know if your pet has worms? 

How can you tell if your pet has worms?
Can you tell when your pet has worms?

The symptoms of worm infections vary depending on the animal. Cats show fewer symptoms compared to dogs. However, more severe infections will cause the following symptoms in both cats and dogs: 

Worms in vomit and stools.

Sometimes adult worms get dislodged by bowel movements and are vomited or passed out in feces. However, it’s common to find segments of tapeworm and eggs in pet’s feces or hanging from the fur around their bottom. Roundworm eggs cannot be seen without a microscope because they’re too tiny. 

Increased appetite and weight loss.

When the worms get to a certain population, they start competing for resources (nutrients) with the host. This loss of nutrients causes the animal’s coat to look dull and brittle. Plus, the animal starts to eat more than usual, yet has little strength for day to day activities.  

Bloated stomach or abdomen.

Common in animals with a severe worm infection. A large number of worms in their gut makes their abdomen look like they just ate.

Vomiting or diarrhea.

The worms interrupt the normal rhythm of the bowel. This upsets the gut and can cause vomiting or diarrhea. 

Blood in feces.

An indication that worms are feeding on the intestinal walls. Blood is released into feces when the worms get dislodged or inflammation is disturbed. 

Coughing and breathing problems.

We’ve already seen that lungworm and heartworm occupy the lungs and blood vessels in the chest areas. They do this by moving around the body until they find a suitable place to lodge. This constant movement causes damage and inflammation which then leads to coughing, pneumonia, and other respiratory problems.

Which of the worms does your pet have?

The intestines provide a comfortable home for most worms – roundworms, hookworms, whipworms, and tapeworms. So when checking for worms that’s the first place to look. 

You can visually inspect your pet’s feces for worms or blood. However, the best way to go about it is to provide a fresh stool sample for your vet to analyze. 

Simply scoop your pet’s feces, place it in a zip lock bag, then take it with you to the vet. They’ll check for worms or worm eggs under a microscope. 


How often should you worm your pet?

How often should you worm your pets?
How often should you worm your pets? | Photo by Eric Rothermel on Unsplash

Puppies and kitties.

It should be presumed that newborn kitties and puppies have worms from their mother’s milk. So they should be wormed from 6 weeks onwards. There are products suitable for pets under 3 weeks old. However, except you’re a breeder or have a nursing mother, you shouldn’t bother yourself with worming a 2 week-old kitty or pup. 

Since young animals are susceptible to worms, you’ll have to worm your puppy or kitty as soon as they’re yours. Start worming at 6 weeks (that’s when you should get them BTW) and every 14 days until they’re 12 weeks old. From the 12th week, you can then worm them every 4 weeks until they’re 20 weeks old. From the 20th week and beyond you can worm them every 3 months. 

Adult dogs and cats.

How often should adult dogs and cats be wormed? 

Well, this depends on the pet, what they do when they’re outside, the place you live, and the vet’s recommendation for your pet. 

Most adult cats and dogs should be wormed every three months, once for each season. During low-risk seasons, for instance, winter, you may not need to deworm your pet. Many vets will advise against it since dewormers are very strong medications.

However, any worms in your pet’s body will still be active so it’s best to stick with the ‘once in three months’ schedule.  

Pregnant and lactating mothers.

Most worming products are not suitable for pregnant and lactating mothers. If you have to worm a nursing animal, it’s best to do so at the end of the pregnancy. Remember, drugs in the mother’s body end up getting sucked by the kitty or pup during breastfeeding. 

Before worming a nursing animal, consult your vet first. They’ll be in a better position to evaluate the animal and prescribe medications suitable for them.    

Does size matter?

Does size matter when worming pets?
Does size matter when worming pets?

The frequency at which a dog or cat is wormed has nothing to do with its size. Large, medium and small cats or dogs get worms which multiple at a similar rate. 

Yes, 50 worms will have more devastating effects on a small dog or cat than a medium or large one. However, it is still 50 worms competing with your pet for food. 

When we talk about size, we’re about the effectiveness of the worming medication. 

A dose that’s okay for a small dog or cat will be under-dose for a larger one. The other way round, it will be an overdose. 

Here’s a quick example: 5 cubes of sugar in a cup of water will be sweet, but 3, 4, 10 cups? It makes little difference. Now, imagine 20 cubes in a cup, that’s how size matters.

Don’t guesstimate. Ask your vet and weigh your pet before medicating your pet! 

How can you prevent your pet from getting worms?

You know, one of the best ways to keep your pet free from worms, fleas, mosquitoes, and other disease-carrying parasites is by keeping your home and yard clean. You’ll also be protecting yourself and your family because some pet worms can be passed to humans. Here are the simple steps you should follow to keep worms at bay: 

  • Ensure to get your dog checked for all kinds of pet worms, for instance, heartworms, at least once a year.
  • Treat flea infestations as soon as you notice them. You can use diatomaceous earth (DE) only, or use a combination of DE and the best flea treatment for pets. Either way, you need to deal with that problem as soon as it crops up.
  • Get your vet to prescribe preventive heartworm medications and give them to your pet at the recommended interval.
  • Wash your hands as often as you can.  

If you’re concerned you might catch worms from your pets, don’t let them kiss or lick you on the face. Does your pet sleep in your bed? Consider moving them to a comfy memory foam bed

What kind of wormer should you use?

What kind of wormer should you use?
Photo by freestocks on Unsplash

There are many different worming treatments and many different ways they can be given to your pet. Your vet will be in the best position to give you advice on which to use for your pet. Some of them are: 

Spot-on wormers.

These worm treatments are applied on the back of the cat or dog’s neck near the base of the skull. You’ve probably done something similar with a topical flea treatment. 


Tablets are usually given to animals directly or dropped in their food. Most worm treatments come in tablets. However, pet owners have mixed results using this method since some pets, especially cats, lose appetite when they discover the tablet. And then you have to learn how to stimulate appetite in a cat that won’t eat.

Paste or granule.

Many pet owners have difficulty administering this form of worm treatment than drops or tablets. However, this option is perfect for pet owners that like to mix worming treatment into their pet’s food – of course, the pet has to like it too. 

Remember to protect your pet from fleas.

Remember to protect your pet from fleas.

Are you aware that a single flea can lay roughly 2,500 eggs in its lifetime? During the warmer months of the year, it’s very easy for one flea to multiply into a nightmare. Heck, you might even get bitten too! 

Since fleas often carry worm larva, eliminating them will reduce not just the fleas biting your pet, but the number of worms in them too. 

Keep that in mind the next time you feel like skipping a flea treatment. 

Regularly use the best flea treatments on your pets to prevent the agony of being bitten hundreds of times daily. 


How often a dog or cat is wormed depends on the animal’s age, its habitat, and the most common parasite in the area.

Irrespective of where you live, there’s always that possibility of your pet getting worms.  

The best thing you can do for their weak little bodies is to prevent worms from accumulating in them and taxing their bodies.