Cat, Dog, Bird, Ferret, Rabbit & Reptile - Fenbendazole

836Why has my veterinary surgeon prescribed this medicine?

Fenbendazole is used to control roundworms and some types of tapeworms; products are available for use in dogs, cats, ferrets, rabbits, birds and reptiles.  Your veterinary surgeon may prescribe fenbendazole for a pregnant bitch to reduce the chance of the puppies being born with worms.  Your veterinary surgeon will advise a deworming programme for your pet.

Fenbendazole is also used for treatment of giardiosis, which is characterised by diarrhoea in dogs and cats.  Giardiosis can potentially be transmitted to humans and your veterinary surgeon will advise you on precautions to take.

Fenbendazole also helps control the intracellular parasite Encephalitozoon cuniculi, which can cause nervous signs, urinary incontinence, eye problems and death in rabbits.  The parasite is transmitted via urine-contaminated food and/or water and measures should be taken to ensure that food and water are placed so as to prevent soiling.

How does this medicine work?

Fenbendazole interrupts parasite energy metabolism by binding to tubulin, thereby disrupting microtubular cell structure and preventing nutrient uptake and other functions.

How do I give this medication?

  • Give this medication to your pet as directed by your veterinary surgeon.  READ THE LABEL CAREFULLY.
  • If the medicine is a liquid, measure the dose with reasonable care.
  • Have a reminder system in place to indicate when the next dose should be given.
  • Try to give this medication at about the same time each day and try not to miss giving any doses.
  • DO NOT give your pet more medicine than directed and DO NOT give more often than directed.
  • Wash your hands after handling the medication.
  • In case of accidental ingestion, seek medical advice immediately and show the package, leaflet or label to the physician.

What if I miss giving a dose?

Give the dose as soon as possible and then resume the dosing programme advised by your veterinary surgeon.  Do not give your pet two doses at once.

How do I store and dispose of this medicine?

Keep this medicine out of reach of children.  Store this medicine in a cool, dry place at less than 25°C.  Store away from heat and direct sunlight.  Do not store this medicine in the bathroom, near the kitchen sink or in damp places.  The medicine may break down if exposed to heat or moisture. Dispose of empty packaging and unused product in your household waste.

Potential side effects

  • Although a drug has possible side effects, it does not mean that there is necessarily a high risk of any of these occurring.
  • There are very few side effects when fenbendazole is given at the usual dose.  If you notice anything unusual, contact your veterinary surgeon.

Possible drug interactions

  • Make sure to tell your veterinary surgeon what other medication you are giving to your pet.
  • Quite often your veterinary surgeon may prescribe two different medications, and a drug interaction may be anticipated.  In this case, your veterinary surgeon may vary the dose and/or monitor your pet more closely.
  • Contact your veterinary surgeon if your pet experiences any unusual reactions when different medications are given together.

© Copyright 2025 LifeLearn Inc. Used and/or modified with permission under license. This content written by LifeLearn Animal Health (LifeLearn Inc.) is licensed to this practice for the personal use of our clients. Any copying, printing or further distribution is prohibited without the express written consent of LifeLearn. This content does not contain all available information for any referenced medications and has not been reviewed by the FDA Center for Veterinary Medicine, or Health Canada Veterinary Drugs Directorate. This content may help answer commonly asked questions, but is not a substitute for medical advice, or a proper consultation and/or clinical examination of your pet by a veterinarian. Please contact your veterinarian if you have any questions or concerns about your pet’s health. Created on Jun 24, 2008.

Brunswick Place Veterinary Clinic

Brunswick Place Veterinary Clinic is a trading name of CVS (UK) Limited; a company which owns over 500 veterinary practices and is registered in England and Wales. Registered number: 03777473. Registered office: CVS House, Owen Road, Diss, Norfolk IP22 4ER.

Location Hours
Monday8:00am – 7:00pm
Tuesday8:00am – 7:00pm
Wednesday8:00am – 7:00pm
Thursday8:00am – 7:00pm
Friday8:00am – 7:00pm
Saturday9:00am – 12:00pm
SundayClosed

*Consulting Times: 9am-6:50pm M-F
From 7pm for any out of hour emergency please contact our out of hours provider: Vets Now Winchester, SO24 9BH Telephone: 01962 807565

In the News