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.

Used and/or modified with permission under license. ©Lifelearn, The Penguin House, Castle Riggs, Dunfermline FY11 8SG


Pet Health Library

Arrowfield Vets are pleased to provide a library of professionally written articles updated by veterinary experts.


Pet Health Checker

Use our Pet Health Checker tool to help you decide if your pet’s symptoms require immediate attention.


Make an Appointment

We are happy to book an appointment for you! Quickly and easily schedule an appointment time that is convenient for you and your pet.