Brand: PANACUR ® EQUINE GRANULES 22% w/w
Company: MERCK ANIMAL HEALTH
DELIVERY FORM: Alfalfa-based pellets, «feed additives and medicated feeds» for oral administration.
ACTIVE INGREDIENT(S): fenbendazole 222 mg/g (equivalent to 22.2%)
CHEMICAL CLASS of the active ingredient(s): benzimidazole
INDICATIONS: HORSES & other equines
PARASITES CONTROLLED (spectrum of activity)
- For the control of large strongyles (Strongylus edentatus, Strongylus equinus, Strongylus vulgaris, Triodontophorus spp.), small strongyles (Cyathostomum spp., Cylicocyclus spp., Cylicostephanus spp.), pinworms (Oxyuris equi), ascarids (Parascaris equorum), and lungworms (Dictyocaulus arnfieldi).
- Panacur is effective for the treatment of migrating strongyle infections and inhibited cyathostome larvae in the large intestine mucosa.
RECOMMENDED DOSE*
* Country-specific differences may apply: read the product label.
- Routine treatment: One sachet per 300 kg bodyweight as a single dose (7.5 mg fenbendazole/kg bodyweight (each gram of Panacur 22.2% granules contains 222 mg fenbendazole).
- Increased dosing for specific infections:
- For the treatment of encysted mucosal small redworm larvae, a dosage of 30 mg fenbendazole/kg should be given.
- For the treatment of migrating stages of Strongylus vulgaris and S. edentatus infestations a dosage rate of 60 mg/kg fenbendazole is recommended. Alternatively, for the treatment of migrating large redworm and encysted mucosal small redworm larvae, administer 7.5 mg/kg fenbendazole daily for five days.
- Where a heavy infestation of Dictyocaulus arnfeldi is present it may be necessary to give 15 mg fenbendazole/kg bodyweight.
Read the product label for specific detail on dosage.
SAFETY
- LD50 (acute oral) in rats: >10000 mg/kg (according to MSDS)
- LD50 (acute dermal) in rats: n.a.
Suspected poisoning? Read the article on fenbendazole safety in this site.
Withholding periods (=withdrawal times) in days for meat & milk (country-specific differences may apply: read the product label)
- Meat and offal: Ireland: 14 days
- Milk: Do not use in mares producing milk for human consumption.
WARNING !!!: Never use on humans, dogs or cats
You may be interested in the following articles in this site dealing with the general safety of veterinary products:
- Safety for humans
- Safety for domestic animals
- Safety for the environment
- Hazard classifications of pesticides
RESISTANCE PREVENTION
Risk of resistance? YES
- Small strongyles (cyathostomes). Resistance of small strongyles to benzimidazoles is widespread and frequent e.g. in the USA, UK and Europe, Argentina, Chile, Uruguay, etc.
- Parascaris equorum: Cases of tolerance to benzimidazoles have been also reported (e.g. in the USA).
This means that if this product does not achieve the expected efficacy against the mentioned parasites, it may be due to resistance and not to incorrect use, which is usually the most frequent cause of product failure.
Alternative chemical classes/active ingredients to prevent resistance of gastrointestinal roundworms through product rotation:
- Imidazothiazoles, mainly levamisole. Not approved for use in horses in many countries.
- Macrocyclic lactones: mainly ivermectin, moxidectin. But tolerance or resistance to these compounds have also been reported in Europe (e.g. in the UK, Germany, Italy), the USA, and Brazil.
- Tetrahydropyrimidines, mainly pyrantel (limited spectrum of activity), but resistance cases have also been reported (e.g. Australia, USA, Brazil, Japan).
- Piperazine. Effective only against certain gastrointestinal roundworms (mainly ascarids).
Learn more about resistance and how it develops.
MARKETING
Are the active ingredients of this product ORIGINAL* or GENERICS**?
- GENERICS
*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 brand/product is marketed: UK, Ireland
GENERIC BRANDS available? Yes, in some countries, but not too many
Click here to learn more about GENERIC vs. ORIGINAL drugs.
Click here for an overview on the most used antiparasitic feed additives and medicated feeds for livestock and horses.
COMMENTS
PANACUR EQUINE GRANULES 22% w/w is an anthelmintic brand for horses containing fenbendazole from MERCK ANIMAL HEALTH .
Fenbendazole is a veteran anthelmintic introduced in the 1970s (by HOECHST, now MSD = MERCK ANIMAL HEALTH). Fenbendazole has a broad-spectrum of activity against roundworms (gastrointestinal and pulmonary) and, depending on the dose also against 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. Fenbendazole is abundantly used worldwide in numberless generic brands for livestock, horses and pets.
As all benzimidazoles (as well as other anthelmintics such as levamisole, monepantel, and tetrahydropyrimidines), fenbendazole for oral administrartion has no residual effect, i.e. it kills the parasites shortly after administration, but as soon as medicated feeding is interrupted it does not significantly protect the animals against re-infestation by infective stages in their environment.
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).
DISCLAIMER
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.