Internal Parasites and Deworming, Pet Care Basics, Shelter and Rescue Resources

Handling Hookworms in Dogs and Cats

Hookworms are ½ inch long, blood-sucking parasites that live in the small intestine. These tiny and thread-like parasites can encyst themselves in the skin, and they will come out during times of illness and stress, such as pregnancy or nursing pups.

Hookworm Transmission in Dogs and Cats

When hookworm eggs are shed in the feces of an infected animal, they take up residence in the environment such as in soil, sand, or litter. After hatching and developing into larvae, they mature and become capable of infecting an animal. Hookworms can infect animals in multiple ways, including through the skin, through ingestion, and through the mother’s milk. Infection typically occurs through ingestion or skin penetration by the larvae.

Hookworms can enter a host through an animal’s feet when it walks across a contaminated environment. When entering through penetration of the skin, the larvae migrate through the bloodstream to the lungs and trachea, where they are coughed up and swallowed. Then they attach themselves to the wall of the small intestine, feed on blood, and lay eggs that pass through the feces.

The larvae can also be ingested through contaminated food, water, or soil or by eating an infected animal. Many of the larvae will travel straight to the intestine, but some may migrate through the body to the lungs where they are coughed up and swallowed.

Lastly, some hookworm larvae can migrate to a nursing animal’s mammary glands, infecting the nursing babies.

Hookworm Symptoms in Dogs and Cats

Depending on the severity of the infestation, symptoms of hookworm in dogs and cats may include vomiting, diarrhea, stunted growth in young animals, a dull or dry coat, coughing, loss of weight, lack of appetite, loss of color in the gums and lips, and occasionally dark, tarry stools. Because hookworms are feeding on the animal’s blood and leaving bleeding sores with their teeth or cutting plates, the animal can rapidly develop anemia, which causes weakness and shortness of breath.

How Do I Know If My Dog Has Hookworm?

Because hookworms are tiny, they are difficult to see without a microscope. Diagnosis is made by looking for eggs in the feces or ELISA testing.

Treatment of Hookworm in Dogs and Cats

Dogs and cats can be treated with a dewormer containing Pyrantel Pamoate, Ivermectin, Milbeymycin Oxime, or Febantel. The animal will need more than one round of treatment because the dewormer only kills the adult worms. When the dewormer kills the adult hookworms, the immature larvae detect the removal of adults in the gut and they will come out of their cysts. Treatment should be repeated every three weeks to kill the adults and the emerging immature larvae as they become adults.

If an animal is severely infected and suffering from anemia, the animal may require supportive care, a high-protein diet, and an iron supplement. Breeder’s Edge B Strong is an excellent supplement that promotes red blood cell formation and boosts anemic pets. In critical cases, blood transfusions may even be necessary.

Keeping infected animals separate from others can help in preventing the worms from spreading further.

How to Prevent Hookworms in Dogs and Cats

Keeping your pets on a monthly preventive will help prevent hookworms. Some heartworm preventives also treat and control hookworm infections. Any newly acquired animal, pregnant dog or cat, puppies, and kittens should be put on a worming schedule. To prevent your pregnant dogs or cats from transferring hookworms to her newborns, you need to implement a worming schedule for your moms. Read Deworming Pregnant Dogs for guidelines on when to worm in these situations.

Proper sanitation and disinfecting is key to preventing hookworms. Picking up feces and keeping the litter box clean are helpful in preventing the spread of these parasites.

If you have more questions on hookworms in dogs or cats or other intestinal parasites, call us at 800.786.4751.

Written by: Marty Greer, DVM

Director of Veterinary Services

Marty Greer, Doctor of Veterinary Medicine, has 40+ years’ experience in veterinary medicine, with special interests in canine reproduction and pediatrics. She received her Doctor of Veterinary Medicine from Iowa State University in 1981. She’s served as Revival’s Director of Veterinary Services since 2019. In 2023, Dr. Greer was named the Westminster Kennel Club Veterinarian of the Year.

If you need help, call us at 800.786.4751.