Signs And Symptoms of Worms in Cats and Dogs - Your Best Friend Pet Boutique

Signs And Symptoms of Worms in Cats and Dogs

Written by Dr. Abdul Basit Javed (DVM, RVMP) for Your Best Friend Pet Boutique

Cats and dogs, like any pets, suffer from a range of health issues, one of which being worms or internal parasites. Worms can infect a number of organs in your pet's body, including the heart, lungs, and intestines. These parasites can lead to multiple symptoms, some of which are apparent while others are subtle.

 In general, all cat and dog owners should be aware of common worm symptoms that most pets exhibit since early diagnosis and treatment can prevent the condition from worsening and save your pet from suffering from major health consequences.

If you are a pet owner who is concerned that your cat or dog may be infected with worms or internal parasites, we can assist. This blog post is a detailed guide to the signs and symptoms of worms in cats and dogs, as well as which worms can infect your pets and how to prevent them, authored by a small animal veterinarian, so read on.

Signs And Symptoms of Worms In Dogs And Cats

If you suspect your pet has worms, it is important to recognize the signs and symptoms, some of which are listed below.

Inconsistent appetite and malnutrition

If your cat or dog has worms, its appetite will become inconsistent. Sometimes your pet's hunger will go away and it will not eat at all, while other times it can suddenly increase to the point where it will eat more food than normal. Despite eating more, your pet will be malnourished and weak.

Progressive weight loss

Worms and internal parasites feed on the nutrients consumed by the dog or cat and some parasites can also feed on the blood of their hosts. All these things combined cause progressive weight loss, and your cat or dog will begin to lose weight while eating considerable amounts of food.

Visible evidence of worms in the stool of your pet

If your dog or cat has worms, particularly intestinal worms such as tapeworms there will be physical evidence of these parasites. You might be able to see worm eggs and segments in your pet's stool, and you may even see actively moving worms as well.

Recurrent diarrhea

If your pet has worms, it will most likely have recurring diarrhea. Diarrhea can potentially cause dehydration in cats and dogs, and in severe cases, they may require IV fluids to recover. Worms can sometimes cause vomiting in addition to diarrhea in pets.

Poor coat

Worms consume the majority of the nutrients in your pet's body and disrupt digestion and other body functions, causing the coat of your dog or cat to become rough and dull, an obvious indicator of worms.


Pale gums

If your pet has internal parasites, heartworms, or lungworms that feed on its blood, it will most likely suffer from anemia (low RBC count), which will cause its gums and eye membranes (conjunctiva) to turn pale.

Distended abdomen

In some cats and dogs, worm infection can cause fluid buildup in the abdomen. Gravity causes fluid to build at the bottom of the abdomen, causing it to distend.

Common Worms That Can Infect Dogs and Cats

Some of the common worms that infect dogs and cats are listed below:

  • Tapeworm
  • Hookworm
  • Roundworm
  • Heartworm
  • Lungworm
  • Whipworm
  • Stomach worm
  • Bladder worm

How To Prevent Worms In Dogs And Cats

  • The following are some of the most effective worm prevention measures for dogs and cats:
  •  Get your dog or cat dewormed on a regular basis at a veterinarian's office.
  •  Clean the litter box and remove your pet's stool on a regular basis.
  •  Don't let your dog or cat consume insects since they commonly carry worm eggs or larvae.
  •  Take your cat or dog to hygienic pet parks.


  1. Everything You Need to Know About Worms in Cats. (n.d.). Small Door Veterinary.
  2. Gillette, L., DVM. (2022, August 24). How to Get Rid of Worms in Cats.
  3. Symptoms of worms in cats and dogs - Beaphar. (n.d.).              


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