A clear, veterinarian-informed guide to the piperazine dewormer for roundworms in dogs, cats, chickens, pigs, and horses — with dosing by species and a free dose calculator.
Roundworm species and dose rates differ by animal. Pick yours for a tailored dosage guide, administration tips, and safety notes.
Toxocara canis & Toxascaris leonina roundworms in dogs and puppies.
Dosage & guide →Toxocara cati roundworms in cats and kittens — a very common feline parasite.
Dosage & guide →Ascaridia galli large roundworm in backyard and flock birds.
Dosage & guide →Parascaris equorum ascarids and pinworms, especially in foals.
Dosage & guide →Ascaris suum, the large roundworm of pigs.
Dosage & guide →Piperazine has been used as a dewormer since the 1950s. Because little is absorbed from the gut and it targets a receptor worms rely on but mammals keep protected in the brain, veterinary references describe it as having a wide margin of safety — one reason it has long been used in young puppies, kittens, and chicks under veterinary guidance.
Works specifically against the large ascarid roundworms that cause pot-bellied puppies and unthrifty poultry.
Described in veterinary references as well tolerated when dosed correctly under veterinary direction.
Made as oral liquids and tablets for pets, and water-soluble powders for flocks and herds.
One of the most economical roundworm treatments available.
The essentials in ten seconds
Vetr WormGard is a piperazine roundworm treatment for dogs and cats. Get it on Vetr, and connect with a licensed veterinarian online to confirm the right choice and dose for your animal.
Piperazine is a dewormer (anthelmintic) that treats large ascarid roundworms — such as Toxocara in dogs and cats, Ascaridia galli in poultry, Ascaris suum in pigs, and Parascaris equorum in horses. It does not treat tapeworms, hookworms, or whipworms.
It acts as a GABA agonist at the worm's neuromuscular junction, causing a reversible flaccid paralysis. The paralyzed worms lose their grip on the gut wall and are passed out in the stool by normal intestinal movement.
Doses depend on species and body weight — roughly 45–65 mg/kg (base) for dogs and cats, and around 100–200 mg/kg for poultry, pigs, and horses, repeated after 1–3 weeks. Use the calculator above as a starting estimate and confirm with your veterinarian.