FORMULATION: «GRANULES» for oral administration, usually mixed with food


CHEMICAL CLASS of the active ingredient(s): BENZIMIDAZOLE


PARASITES CONTROLLED* (spectrum of activity):



  • Administer 100 mg fenbendazole per 1kg (2.2lb) bw as a single dose.
  • Each 1g sachet/dose treats 2kg (4.4lb) bw as a single dose.
  • Frequency of treatment depends on the indication

* Can be slightly different in some countries: read the product label!


  • LD50 (acute oral) in rats: n.a. for the granules. >10000 mg/kg for fenbendazole a.i.
  • Estimated Hazard Class according to the WHO: not applicable for veterinary medicines

Suspected poisoning? Read the articles on fenbendazole safety in this site.

You may be interested in the following articles in this site dealing with the general safety of veterinary products:


Risk of resistance development? LOW

There are no reports on resistance of dog or cat worms to benzimidazoles about 40 years after their introduction.

Learn more about resistance and how it develops.


Are the active ingredients of this product ORIGINAL* or GENERICS**?

  • Fenbendazole: GENERIC (introduced in the 1970s)

*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this product is marketed: UK.
GENERIC BRANDS available? YES, in most countries. EASY WORMER GRANULES from JOHNSON'S VETERINARY is itself a generic version of PANACUR C from Merck Animal Health.

Click here to learn more about GENERIC vs. ORIGINAL drugs.


EASY WORMER GRANULES is a cat wormer from JOHNSON'S VETERINARY containing fenbendazole, a generic version of MERCKS's PANACUR C.

Fenbendazole is a veteran benzimidazole introduced in the 1970s (by HOECHST). It is a broad-spectrum anthelmintic effective against most gastrointestinal worms that infect pets. Depending on the dose this includes roundworms (Toxocara cati, Toxascaris leonina), hookworms (Ancylostoma spp, Uncinaria stenocephala), lungworms (Aelurostrongylus abstrusus) and certain tapeworms (e.g. Taenia spp). It is abundantly used in livestock and horses, moderately in pets. It is not used in agriculture.

Fenbendazole and most other benzimidazoles (e.g. febantel, albendazole, mebendazole, etc.) and tetrahydropyrimidines (e.g. pyrantel, morantel, etc.) have no residual effect, i.e. they act against the worms during a few hours after administration but are quickly metabolized and excreted. For this reason treatment must often be repeated for certain indications. This is in contrast with wormers containing macrocyclic lactones (e.g. milbemycin oxime, selamectin) that ensure protection against numerous roundworms during weeks after a single treatment.

For an overview and a list of the most popular pet wormers click here.


This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.