Panacur Suspensie 2.5%.

Panacur Suspensie 2.5%.

DELIVERY FORM: «drench» for oral administration.
 

Sheep

• Roundworms:  

  • Gastrointestinal roundworms (adults & immatures): Ostertagia spp, Haemonchus spp, Trichostrongylus spp, Nematodirus spp, Cooperia spp, Chabertia spp, Oesophagostomum spp, Strongyloides spp, Trichuris spp (variable efficacy).

  • Lungworms: of Dictyocaulus filaria.

• Tapeworms: Moniezia spp.

RECOMMENDED DOSE*

* Country-specific differences may apply: read the product label.

• Sheep: 1 mL product/5 kg bw (equivalent to 5.0 mg of fenbendazole/kg).
  Thoroughly shaking suspensions before use is crucial for efficacy. If the active ingredient remains in the sediment, a few animals may get most of the active ingredient and will be overdosed, and the large majority will get almost only solvents and will be underdosed.

ACTIVE INGREDIENT(S): fenbendazole 25 mg/mL (equivalent to 2.5%). This formulation contains also 0.4 mg/mL elemental selenium and 0.94 mg/mL elemental cobalt.

CHEMICAL CLASS of the active ingredient(s): benzimidazole
 

Withholding periods (=withdrawal times) in days for meat & milk (country-specific differences may apply: read the product label)

• Meat: UK 15 days.

• Milk for human consumption: UK 7 days

WARNING !!!: Never use on humans, dogs and cats.
 

PANACUR is the original brand for products containing fenbendazole introduced already in the 1970s by HOECHST (later acquired by INTERVET, now MERCK MSD ANIMAL HEALTH = MSD ANIMAL HEALTH).

All benzimidazoles are veteran anthelmintics. Fenbendazole has a broad-spectrum of activity against roundworms (gastrointestinal and pulmonary) & tapeworms, but is ineffective against flukes. Fenbendazole also kills eggs of roundworms (ovicidal activity). As all benzimidazoles, fenbendazole has no efficacy whatsoever against external parasites (ticks, flies, lice, mites, etc). Among the benzimidazoles fenbendazole is quite comparable with oxfendazole in terms of efficacy and safety.

As all benzimidazoles (as well as other anthelmintics such as levamisole, monepantel, and tetrahydropyrimidines), fenbendazole administered as a drench has no residual effect, i.e. it kills the parasites shortly after administration, but does not significantly protect the animals against re-infestation by infective stages in their environment.

Fenbendazole is abundantly used worldwide in numberless generic brands for livestock, horses and pets.

Drench is the preferred delivery form for use on cattle, sheep and goats, but in many countries it is also available in the form of feed additives (mainly for pig & poultry) and other delivery forms for oral administration (boluses, tablets, pastes, etc). As most benzimidazoles it is not appropriate for intramuscular or subcutaneous injection due to its poor solubility in water, but intraruminal injection is very popular in Latin America.

Both for livestock and pets fenbendazole is often used in combinations that broaden the spectrum of activity or try to overcome potential resistance. Typical mixtures for livestock include a flukicide (e.g. closantel, etc.) and/or a macrocyclic lactone, and/or levamisole, although such mixtures are not approved everywhere. For dogs and cats it is often combined with a taenicide (e.g. praziquantel).

Unfortunately, resistance of several gastrointestinal roundworms to all benzimidazoles (including fenbendazole) is already very high and very frequent worldwide in sheep and goats, slightly lower in cattle, which has significantly reduced their usage in livestock. Nowadays more convenient pour-ons and injectables containing macrocyclic lactones (e.g. abamectin, doramectin, eprinomectin, ivermectin, moxidectin) are often preferred over drenches with benzimidazoles. Macrocyclic lactones also ensure several weeks protection against re-infestation by several worm species, in contrast with all benzimidazoles that lack any residual effect.
 

In ruminants, reducing the amount of feed slows down the exit flow of the rumen and prolongs the time during which the active ingredient remains there and is absorbed. Consequently it is advisable to reduce the access of animals to feed (especially to fresh pasture, not to water) 24 hours before administration. For the same reason, it is better to keep the animals away from food for about 6 hours after drenching. However sick or weak animals should not be kept away from food and fasting animals should have access to water. In cattle, a fiber-rich diet also increases the bioavailability of fenbendazole.

Fenbendazole active ingredient is a solid compound poorly soluble in water and in drenches it is formulated as a suspension (not as a solution or as an emulsion). A key unfavorable feature of all suspensions is that the suspended solid particles tend to fall down to the bottom of the container and sediment, very much like sand in water. This means that suspensions must be thoroughly shaken before use. How fast the suspension sediments and how easily shaking the container redistributes the suspension depends on the formulation quality. A good formulation sediments slowly and shaking will re-suspend it quickly. Bad formulations sediment quickly and shaking re-suspends them slowly.