Fenbendazole (Panacur®, Safe-Guard®) for Dogs and Cats
Anna-av/iStock/Getty Images Plus via Getty Images
Fenbendazole is a deworming medication that veterinarians use to treat several types of intestinal parasites in dogs and cats.
It’s commonly sold under the brand names Panacur® and Safe-Guard® and may also be prescribed extra-label for certain parasites.
Here’s how fenbendazole works, what parasites it treats, possible side effects, dosing information, and important safety considerations.
Key Takeaways
- Fenbendazole treats several intestinal parasites in dogs and is commonly prescribed extra-label for cats.
- It is available under the brand names Panacur® and Safe-Guard®.
- Fenbendazole is best given with food and exactly as directed by your veterinarian.
- Most dogs and cats tolerate fenbendazole well, and side effects are uncommon.
- Your veterinarian may recommend follow-up fecal testing to confirm the parasites have been eliminated.
What Is Fenbendazole Used for in Dogs and Cats?
Fenbendazole is a deworming medication used to treat several types of intestinal parasites in dogs and, under veterinary guidance, certain parasites in cats.
Fenbendazole treats:
- Roundworms
- Hookworms
- Whipworms
- Tapeworms
- Some protozoal parasites, including Giardia
Fenbendazole is available as oral granules, liquids, chewable tablets, and capsules under the brand names Panacur® and Safe-Guard®.
Some formulations are available over the counter, while others require a prescription from your veterinarian.
Is Fenbendazole FDA-Approved?
Fenbendazole is FDA-approved for use in dogs to treat roundworms, hookworms, whipworms, and tapeworms.
It is also FDA-approved to treat a variety of parasitic worms in horses, cattle, swine, and goats.
Fenbendazole is not FDA-approved as a veterinary medication for cats, ferrets, or certain other species. However, veterinarians may legally prescribe it extra-label (off-label) when they determine it is appropriate for an individual patient.
Talk with your veterinarian about whether fenbendazole is the right treatment for your pet.
Compounded Fenbendazole
In some situations, your veterinarian may recommend a compounded formulation of fenbendazole if an FDA-approved product is not the best option for your pet.
Compounded medications may be prescribed when:
- Your pet has difficulty taking the commercially available formulation.
- The required dosage strength is not commercially available.
- Your pet is allergic to an ingredient in the FDA-approved medication.
Compounded medications are not FDA-approved. They are prepared by a veterinarian or licensed pharmacist to meet an individual patient's specific needs.
Safety Considerations for Fenbendazole
Fenbendazole is well tolerated by most dogs and cats, but it should be used with caution in some pets and may not treat every type of parasite.
Before giving fenbendazole, tell your veterinarian if your pet:
- Has a known sensitivity or allergy to fenbendazole
- Is taking other medications, vitamins, or supplements that could interact with treatment
- Has any underlying medical conditions that could affect medication safety
Fenbendazole does not treat all parasites, including the tapeworm spread by fleas. If parasites are still present after treatment, your veterinarian may recommend a different deworming medication.
Your veterinarian may also perform follow-up fecal testing to confirm the medication is working and determine whether parasites are still present.
How Fenbendazole Works
Fenbendazole works by preventing certain parasites from producing the energy they need to survive, ultimately killing the worms.
By disrupting the parasites' ability to produce energy, fenbendazole causes them to die and be eliminated from the body.
In some types of worms, fenbendazole may also affect immature life stages, including larvae and eggs.
How To Give Fenbendazole to Dogs and Cats
Give fenbendazole exactly as directed by your veterinarian. It is best absorbed when given with food.
Administration tips:
- Follow the directions on the prescription label or those provided by your veterinarian.
- Give fenbendazole with food to help maximize absorption.
- Many puppies are routinely dewormed after weaning at 6, 8, 10, and 12 weeks of age. The nursing mother dog should also be dewormed.
- Adult dogs may require deworming twice a year or whenever parasites are present.
- Your veterinarian will recommend the most appropriate deworming schedule for your pet.
Missed a Dose?
If you miss a dose of fenbendazole, contact your veterinarian for guidance. In many cases, they may recommend giving the missed dose when you remember.
However, if it is almost time for your pet's next scheduled dose, they may advise skipping the missed dose and resuming the normal dosing schedule.
Do not give extra or double doses.
Fenbendazole Side Effects
Fenbendazole is generally well tolerated by dogs and cats when used as directed, and side effects are uncommon.
Possible side effects in dogs include:
- Vomiting
- Excessive drooling
- Diarrhea
- Allergic reaction (anaphylaxis), including hives, facial swelling, lethargy, difficulty breathing, and collapse
Contact your veterinarian if your dog develops stomach upset. Seek emergency veterinary care immediately if you suspect your dog is having an allergic reaction.
Studies have shown that fenbendazole is also well tolerated in cats. Some cats may develop temporary soft stools, which usually resolve on their own.
Human Side Effects
Fenbendazole is a prescription veterinary medication and is not intended for human use.
- Wash your hands after handling the medication.
- Humans should never take medication prescribed for pets, and pets should never receive medication prescribed for people.
- Fenbendazole doses for people and pets are different.
If you accidentally ingest fenbendazole, seek medical attention or call Poison Control at 800-222-1222.
Monitoring Your Pet
No specific monitoring is required while your pet is taking fenbendazole. However, your veterinarian may recommend routine testing based on your pet's health, other medications, or the condition being treated.
When To Call Your Veterinarian
Contact your veterinarian if:
- Your pet develops severe side effects.
- Your pet's condition worsens or does not improve with treatment.
- You suspect your pet has received an overdose.
- You have additional questions or concerns about using fenbendazole.
Fenbendazole Overdose
A single overdose of fenbendazole is unlikely to cause toxicity in dogs or cats. However, any suspected overdose should be treated as a veterinary emergency.
Fenbendazole has a wide margin of safety in cats. In dogs, repeated large overdoses over an extended period may cause bone marrow suppression, resulting in abnormally low blood cell counts.
If you suspect your pet has received an overdose, seek emergency veterinary care immediately or contact an animal poison control center. Consultation fees may apply.
- Pet Poison Helpline: (855) 764-7661
- ASPCA Animal Poison Control: (888) 426-4435
How To Store Fenbendazole for Dogs and Cats
Store fenbendazole according to the prescription label to help maintain its safety and effectiveness.
Storage instructions:
- Always follow the storage instructions on the prescription label.
- Store compounded formulations according to the instructions provided by the compounding pharmacy.
- Store fenbendazole at room temperature, at or below 77 F (25 C).
- Do not freeze the medication.
- Keep the container tightly closed to protect it from moisture and light.
- Keep out of reach of children and pets.
Fenbendazole for Dogs and Cats FAQs
How much fenbendazole can I give my dog?
The correct dose of fenbendazole depends on your dog's weight and the condition being treated.
Always follow the directions on the prescription label and your veterinarian's instructions. Your veterinarian will determine the appropriate dose based on your dog's individual needs.
How long does it take for fenbendazole to work for a Giardia infection?
Fenbendazole is commonly prescribed for three to five days to treat Giardia, although the length of treatment may vary depending on your pet's response.
Because Giardia can spread from pets to people, it's important to follow your veterinarian's instructions carefully.
Your veterinarian may also recommend bathing your pet during treatment and performing a follow-up fecal test to confirm the infection has cleared.
What kind of worms does fenbendazole kill?
Fenbendazole treats roundworms, hookworms, whipworms, and tapeworms in dogs.
Veterinarians may also prescribe fenbendazole to treat other parasites, including Giardia and lungworms, when appropriate.
How long does fenbendazole take to work in cats?
Fenbendazole is not FDA-approved for use in cats, but veterinarians may prescribe it extra-label to treat certain parasites.
Treatment length varies depending on the parasite being treated. Follow your veterinarian's instructions for dosing and duration.
Can I use fenbendazole prescribed for horses on my dog?
No. Never give horse fenbendazole products to dogs.
Horse formulations are much more concentrated than dog formulations and can increase the risk of an overdose.
Is Panacur® the same as fenbendazole?
Yes. Panacur® is a brand name for the active ingredient fenbendazole.
Can fenbendazole be given with food?
Yes. Fenbendazole is best absorbed when given with food.
Is fenbendazole available over the counter?
Yes. Some fenbendazole products are available over the counter, while other formulations may require a prescription from your veterinarian.
No vet writer or qualified reviewer has received any compensation from the manufacturer of the medication as part of creating this article. All content contained in this article is sourced from public sources or the manufacturer.
