Lungworm, explained — and how to treat it.
A clear, vet-reviewed guide to lungworm infection in dogs, cats, horses and livestock: how animals catch it, the warning signs, and the dewormers that clear it.
Parasites that live where the air is
Lungworms are parasitic roundworms (nematodes) that make their home in the airways, lung tissue or nearby blood vessels of their host. As the adult worms feed and lay eggs, they irritate the respiratory tract — triggering the coughing, wheezing and breathlessness that give the group its name.
Animals usually pick up the parasite by eating an infected slug, snail or small prey animal, or by grazing pasture contaminated with larvae. From the gut, the immature worms migrate through the body to reach the lungs, where they mature and complete the cycle.
Most lungworm infections are treatable with the right dewormer. The key is catching them early and matching the medication to the species involved.
Lungworm Dosage Calculator
Estimate a fenbendazole dose by species and bodyweight.
Educational estimate only — not a prescription. Lungworm treatment varies by parasite and patient. Always confirm the dose and course with your veterinarian.
Different animals, different worms
“Lungworm” covers several parasite species. The signs, risk and treatment depend on which animal — and which worm — you’re dealing with.
Dogs
Angiostrongylus, Crenosoma & Oslerus lungworm in dogs.
Read about dogs →Cats
Aelurostrongylus abstrusus, the feline lungworm.
Read about cats →Horses
Dictyocaulus arnfieldi and the donkey connection.
Read about horses →Cattle
Dictyocaulus viviparus, the cause of husk / hoose.
Read about cattle →Sheep & Goats
Dictyocaulus, Muellerius and Protostrongylus.
Read about sheep & goats →Common warning signs of lungworm
Symptoms range from a nagging cough to serious breathing difficulty. They can build slowly, so they’re easy to mistake for a cold or allergy.
Persistent cough
A dry or productive cough that lingers for weeks, often worse after exercise.
Laboured breathing
Wheezing, rapid breathing or shortness of breath as airways become inflamed.
Tiredness & weight loss
Reduced energy, poor appetite and weight loss as the body fights infection.
Bleeding issues
In dogs, some lungworms can interfere with clotting — a sign that needs urgent vet care.
The lungworm life cycle
Most lungworms rely on slugs and snails as a stepping-stone host. Understanding the loop is the key to breaking it.
Treating a lungworm infection?
VETR carries veterinarian-trusted dewormers and oral suspensions shipped fast. Match the right product to your animal and parasite.
Shop dewormers at VETR →Practical how-to guides
Plain-language walkthroughs for the moments that matter — treating, dosing and preventing.
Treat lungworm in dogs
The right order of operations, from diagnosis to dewormer to follow-up.
Read the guide →Give a liquid dewormer
The syringe technique that gets the full dose into a dog or cat, mess-free.
Read the guide →Prevent it year-round
A simple seasonal plan to break the slug-and-snail cycle for good.
Read the guide →Where to next?
How it’s diagnosed
The Baermann test, faecal checks, imaging and what your vet looks for.
Diagnosis guide →Treatment options
The dewormers used against lungworm and how a course typically works.
Treatment guide →Preventing reinfection
Routine worming, slug control and habits that keep lungworm away.
Prevention guide →