Dog Hookworm: Symptoms, Treatment, and Prevention

Hookworms are thin, blood-feeding intestinal parasites that attach to a dog’s intestinal wall and can cause anemia, weight loss, and in puppies, severe or even life-threatening illness. This guide explains how dogs get hookworms, how to recognize the signs, and how treatment and prevention work.

This guide is for informational purposes. Always contact a licensed veterinarian for diagnosis and treatment of your pet’s health concerns.

In This Guide:

What Are Hookworms?
Symptoms of Hookworm Infection
How Dogs Get Hookworms
Diagnosis and Treatment
Prevention and Human Risk
Frequently Asked Questions

What Are Hookworms?

Hookworms (most commonly Ancylostoma caninum in dogs) are small, thin roundworms that attach to the lining of the small intestine using hook-like mouthparts and feed on the dog’s blood. Unlike tapeworms, which are visible as rice-like segments, hookworms are microscopic and are usually only detected through a fecal test.

Because hookworms actively feed on blood, heavy infestations can cause significant blood loss — this is especially dangerous in puppies, whose smaller blood volume makes them vulnerable to severe anemia within days of infection.

Symptoms of Hookworm Infection

Symptoms vary depending on the severity of infestation and the age of the dog. Puppies typically show more severe signs than adult dogs, who may carry a low-level infection with few visible symptoms.

Severity	Symptoms
Mild	Dull coat, mild weight loss, occasional soft stool
Moderate	Dark, tarry, or bloody stool, pale gums, lethargy, poor appetite
Severe (common in puppies)	Severe anemia, weakness, collapse, failure to thrive

Skin irritation, redness, and itching between the toes can also occur when hookworm larvae penetrate the skin directly, which is a separate route of infection from ingestion.

How Dogs Get Hookworms

Dogs can become infected with hookworms through several routes:

Ingestion: Swallowing larvae from contaminated soil, grass, or feces.
Skin penetration: Larvae in soil can burrow directly through a dog’s paw pads or skin.
Nursing: Puppies can be infected through their mother’s milk, which is why puppies are often dewormed starting at just 2 weeks of age.
In utero: Some hookworm species can be transmitted to puppies before birth.

Hookworm eggs are shed in feces and can survive in soil for weeks to months under the right conditions, making contaminated parks, yards, and kennels a common source of reinfection.

Diagnosis and Treatment

Hookworms are diagnosed through a fecal flotation test performed by a veterinarian, which detects microscopic eggs in the stool. Because a single negative test doesn’t always rule out infection (especially early on), vets may recommend repeat testing if symptoms persist.

Treatment typically involves a course of deworming medication (such as pyrantel pamoate, fenbendazole, or milbemycin oxime), often repeated after 2–3 weeks to kill any newly hatched worms the first dose missed. Severely anemic dogs, especially puppies, may require supportive care such as iron supplementation or, in extreme cases, a blood transfusion.

If you suspect your dog has hookworms, contact your local veterinarian promptly — early treatment significantly improves outcomes.

Prevention and Human Risk

Preventing hookworm infection involves a combination of routine deworming, environmental management, and monthly parasite prevention:

Monthly heartworm/parasite preventives: Many monthly heartworm medications also protect against hookworms — ask your vet which product covers this.
Prompt waste cleanup: Picking up feces quickly reduces environmental contamination and reinfection risk.
Routine fecal testing: Annual or biannual fecal exams catch low-level infections before they cause visible illness.
Puppy deworming schedule: Following your vet’s recommended deworming schedule for puppies (typically starting at 2 weeks and repeated every 2 weeks until 12 weeks old) is critical.

Important human health note: Hookworm larvae can penetrate human skin (a condition called cutaneous larva migrans), typically causing an itchy, winding rash — most often from walking barefoot in contaminated soil or sand. Wearing shoes in areas frequented by dogs and washing hands after yard work or cleanup are sensible precautions.

Can humans get hookworms from dogs?

Yes, hookworm larvae can penetrate human skin and cause a condition called cutaneous larva migrans, resulting in an itchy, winding rash. This typically happens from walking barefoot on contaminated soil or sand rather than direct contact with an infected dog.

How do I know if my dog has hookworms?

Common signs include dark or bloody stool, pale gums, weight loss, lethargy, and poor appetite, though many dogs show subtle or no symptoms with mild infections. A fecal flotation test performed by a veterinarian is the only reliable way to confirm hookworm infection.

How are hookworms in dogs treated?

Hookworms are treated with a course of deworming medication such as pyrantel pamoate or fenbendazole, typically given as an initial dose followed by a repeat dose 2–3 weeks later. Severely affected puppies may also need supportive care for anemia.

Are puppies more at risk from hookworms?

Yes, puppies are significantly more vulnerable to hookworms because their smaller blood volume makes them susceptible to severe anemia, and they can be infected in utero or through their mother’s milk. This is why veterinarians recommend deworming puppies starting as early as 2 weeks of age.

How can I prevent my dog from getting hookworms?

Monthly parasite preventives that cover hookworms, prompt cleanup of feces, routine fecal testing, and following your vet’s puppy deworming schedule are the most effective prevention strategies. Avoiding areas with heavy fecal contamination also reduces exposure risk.

If your dog is showing signs of hookworm infection, don’t wait — HeiBob’s local veterinarian directory can help you find trusted care nearby.