Brand: OXFENCARE Oral Suspension
FORMULATION: «drench» for oral administration.
ACTIVE INGREDIENT(S): Oxfendazole: 22.65 mg/mL (= 2.265%)
CHEMICAL CLASS of the active ingredient(s): benzimidazole
INDICATIONS: CATTLE & SHEEP
PARASITES CONTROLLED* (spectrum of activity)
* Country-specific differences may apply: read the product label.
- Gastro-intestinal roundworms (mature & immature): Haemonchus spp, Ostertagia spp, Trichostrongylus spp, Nematodirus spp (incl. Nematodirus battus, Cooperia spp, Oesophagostomum spp, Chabertia spp, Trichuris spp spp, Capillaria spp.
- Lungworms: Dictyocaulus spp.
- Tapeworms: Moniezia spp.
* Country-specific differences may apply: read the product label.
- Cattle: 10 ml product/50 kg bw, equivalent to ~4.5 mg/kg oxfendazole per kg bw.
- Sheep: 1 ml product/5 kg bw, equivalent to 5 mg/kg oxfendazole per kg bw.
Read the product label for further details on dosing
- LD50 (acute oral) in rats: oxfendazole: a.i. >6400 mg/kg
- LD50 (acute dermal) in rats: n.a.
Suspected poisoning? Read the article on oxfendazole safety in this site.
Withholding periods (=withdrawal times) for meat & milk (country-specific differences may apply: read the product label)
- Meat: Ireland: 28 days;
- Milk: Ireland: Milk intended for human consumption may only be taken from cows after 4 days from the last treatment. Do not use in sheep 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
Risk of resistance: YES.
Resistance of gastrointestinal roundworms to all benzimidazoles (incl. oxfendazole) in ruminants is a very serious and increasing problem worldwide, particularly in sheep and goats, but also in cattle. The most affected worm species are:
- Sheep & goats: Haemonchus spp, Ostertagia spp /Teladorsagia spp, Trichostrongylus spp, Nematodirus spp, Chabertia ovina.
- Cattle: Cooperia spp, Haemonchus spp, Ostertagia spp, Trichostrongylus spp, Oesophagostomum
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:
- Derquantel: available so far only in some countries for sheep in combination with abamectin.
- Macrocyclic lactones (e.g. abamectin, doramectin, eprinomectin, ivermectin, moxidectin, etc.): only against gastrointestinal roundworms, ineffective against flukes or tapeworms. Resistance to macrocyclic lactones is also increasing and strengthening quickly in many countries.
- Levamisole: only against gastrointestinal roundworms, ineffective against flukes or tapeworms. Resistance to levamisole has been reported in most countries, but is usually less strong and frequent than to benzimidazoles.
- Monepantel: only against gastrointestinal roundworm species in sheep & goats in some countries (e.g. Australia, UK & EU, New Zealand). First cases of resistance reported in New Zealand in 2013. Ineffective against flukes or tapeworms.
- Salicylanilides (e.g. closantel, niclosamide, rafoxanide): only in some countries against liver flukes, certain gastrointestinal roundworm species or tapeworms. Resistance to closantel has been reported in some countries. Not available in all countries.
- Tetrahydropyrimidines (e.g. morantel, pyrantel): only against certain gastrointestinal roundworms, ineffective against flukes or tapeworms. Not available in some countries. Resistance to morantel has been reported in some countries.
- Nitroxinil: only against liver flukes (Fasciola hepatica) and a few gastrointestinal roundworms (e.g. Bunostomum spp, Haemonchus spp, Oesophagostomum spp). Not available in some countries. Ineffective against tapeworms
These alternative products may not be available in all countries or may not be available as drenches.
There are only very few reports on resistance of Moniezia spp tapeworms to benzimidazoles (e.g. fenbendazole) but it is certainly not yet a widespread problem.
Learn more about resistance and how it develops.
Are the active ingredients of this product ORIGINAL* or 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: Ireland
GENERIC BRANDS available? Yes, but not a lot in most countries, if at all.
Click here to learn more about GENERIC vs. ORIGINAL drugs.
For an overview on the most used antiparasitic drenches click here.
OXFENCARE is a classic anthelmintic drench for sheep with generic oxfendazole from ANCARE.
Oxfendazole is a veteran broad-spectrum benzimidazole (introduced in the 1970s by WELLCOME, SYNTEX). It is effective against roundworms (gastrointestinal and pulmonary) & tapeworms, but is ineffective against flukes. Oxfendazole also kills eggs of roundworms (ovicidal activity). As all benzimidazoles, oxfendazole has no efficacy whatsoever against external parasites (ticks, flies, lice, mites, etc). Among the benzimidazoles oxfendazole is quite comparable with fenbendazole in terms of efficacy and safety. It is moderately used in livestock, scarcely in horses and pets. It is not used in agriculture.
As all benzimidazoles (as well as other anthelmintics such as levamisole, monepantel, and tetrahydropyrimidines), oxfendazole 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.
Nowadays more convenient pour-ons and injectables containing macrocyclic lactones (e.g. abamectin, doramectin, eprinomectin, ivermectin, moxidectin) are often preferred over drenches with benzimidazoles or combinations. 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.
As most benzimidazoles, oxfendazole active ingredient is 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.
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.
Click here for general information on good practices for the prevention and control of gastrointestinal worms in livestock.
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.