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Dosage tool
Dog dewormer dosage calculator
Enter your dog's weight to estimate the standard fenbendazole whipworm dose — the active ingredient in Panacur® and Safe-Guard®. It uses the FDA label rate of 50 mg/kg once daily for 3 consecutive days. This is an educational estimate, not a prescription.
Fenbendazole dose estimator
FDA-labeled rate: 50 mg/kg (22.7 mg/lb), once daily for 3 consecutive days.
Use your dog's current weight. Puppies must be at least 6 weeks old for fenbendazole.
How the calculator works
Fenbendazole for whipworms is dosed by body weight at the labeled rate of 50 milligrams per kilogram (about 22.7 mg per pound), given once daily for 3 consecutive days. The calculator converts your dog's weight to kilograms, multiplies by 50 to get the estimated daily dose in milligrams, and multiplies that by three for the course total.
It also estimates Safe-Guard® 22.2% granules, whose label is roughly 1 gram of granules per 10 pounds of body weight per day. Products differ in concentration, so the granule figure is a starting reference, not a substitute for the directions on the package you actually have.
Worked example
For a 50 lb dog: 50 ÷ 2.2046 ≈ 22.7 kg. At 50 mg/kg that is about 1,134 mg per day, or roughly 3,402 mg over the 3-day course. Using the granule rule of thumb, about 5 grams of Safe-Guard® 22.2% granules per day. Your veterinarian confirms the exact product and amount.
Why you still need a veterinarian
- Diagnosis first. The signs of whipworms overlap with other intestinal problems; the right treatment depends on the right diagnosis.
- Product and concentration vary. Liquids, pastes, granules and tablets are not interchangeable milligram-for-milligram.
- Age, weight and health matter. Puppies must be at least 6 weeks old, and sick or pregnant animals need tailored advice.
- The schedule is the hard part. A single course rarely finishes the job — the repeats across ~3 months are what actually clear the infection.
Common dosing questions
What is the fenbendazole dose for whipworms in dogs?
The labeled rate is 50 mg/kg (about 22.7 mg/lb) by mouth once daily for 3 consecutive days, repeated at about 3 weeks and 3 months. Confirm the product and amount with your veterinarian.
Can I use this calculator for a cat?
No. Fenbendazole isn't FDA-approved for cats and true whipworm infection is rare in cats with no firmly established treatment. The calculator intentionally won't produce a feline dose — see a veterinarian for cat parasite care.
How much Safe-Guard® do I give my dog?
For the 22.2% granules, the label works out to about 1 gram of granules per 10 lb of body weight per day for 3 days. Always follow the directions on your specific package and your vet's guidance.
Is one 3-day course enough?
Usually not on its own. Because eggs keep maturing for about 12 weeks, the course is repeated at ~3 weeks and ~3 months, or followed by a monthly preventive that controls whipworms.
Confirm the dose before you treat.
A licensed vet on Vetr can verify your dog's weight-based dose, pick the right product, and deliver it to your door — then set the repeat schedule that actually clears whipworms.
References
This page is general educational information, not veterinary advice. It is compiled and kept consistent with these veterinary sources:
- American Kennel Club — Whipworms in Dogs: Signs, Symptoms, Treatments.
- Cornell University College of Veterinary Medicine, Riney Canine Health Center — Whipworms in dogs.
- Merck Veterinary Manual — Whipworms in Small Animals.
- VCA Animal Hospitals — Whipworm Infections in Dogs.
- U.S. FDA, Center for Veterinary Medicine — fenbendazole label dose and extra-label safety letter.