Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Panacur C is an over-the-counter dewormer for dogs containing fenbendazole. It’s labeled to treat roundworms, hookworms, whipworms, and one type of tapeworm (Taenia), given daily for three days. It does not treat the common flea tapeworm (Dipylidium) and doesn’t prevent heartworm. A fecal test helps you know what you’re treating, and monthly heartworm preventives often cover common intestinal worms too.
What it treats
- Roundworms
- Hookworms
- Whipworms
- Taenia tapeworms (from hunting or eating prey)
Vets also sometimes use fenbendazole for Giardia, as an extra-label treatment under their direction.
What it doesn’t cover
- Flea tapeworms (Dipylidium), which need praziquantel or epsiprantel, plus flea control
- Heartworm
- Protozoa like coccidia
Using it
- Weigh your dog to choose the right amount
- Mix with food daily for three consecutive days
- Follow up with a fecal test if signs persist
Alternatives
- Monthly heartworm preventives that include intestinal worm coverage
- Prescription dewormers chosen by your vet after a fecal test
- Combination products that cover tapeworms
See a vet if
- Your puppy has diarrhea, a pot belly, or poor growth
- You see worms or rice-like segments in stool
- Diarrhea continues after treatment
Sources
- Merck Animal Health: Panacur C (fenbendazole) product label
- Companion Animal Parasite Council (CAPC): Canine guidelines
- Merck Veterinary Manual: Anthelmintics
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.