DELIVERY FORM: slow-release capsule for oral administration.


  • Albendazole 4.62 g per capsule
  • Selenium 24 mg  (as sodium selenate) and Cobalt 118 mg (as cobalt sulphate heptahydrate), without any anthelmintic efficacy.

CHEMICAL CLASS of the active ingredient(s):


PARASITES CONTROLLED (spectrum of activity)


For 100 days continuous protection against the following helminths susceptible to benzimidazole-type anthelmintics:


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

One capsule per animal weighing 40 to 80 kg.


  • LD50 (acute oral) in rats: Albendazole: 2400 mg/kg (for the a.i.) (source MSDS)

Suspected poisoning? Read the article on albendazole safety in this site.

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

  • Meat: NIL (ESI 60 days)
  • Milk for human consumption: Do not use in female sheep which are producing, or may in the future produce, milk or milk products 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:


Risk of resistance? YES

Unfortunately, resistance of several gastrointestinal roundworms to albendazole (and other benzimidazoles) is already very high and very frequent worldwide in sheep and goats.

This means that if this product does not achieve the expected efficacy against the mentioned parasites, it can 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:

These alternative products may not be available in all countries or may not be effective against all the concerned parasites.

It is highly recommended to periodically check the resistance status of each property performing appropriate tests (e.g. fecal egg counts) under supervision of a veterinary doctor. Such tests are now routinely available for most producers in developed countries.

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: Australia, New Zealand
GENERIC BRANDS available? Not in the form of capsules so far. Several drenches with a comparable composition.

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

For an overview on the most used drench or capsule brands for livestock click here.


EXTENDER SECO is a slow-release capsule brand with albendazole.

Albendazole, another veteran anthelmintic (introduced in the 1970s by SMITH-KLINE) was the first benzimidazole with a broad-spectrum of activity, i.e. it shows a dose-dependent efficacy against all three major classes of parasitic worms: Roundworms (gastrointestinal and pulmonary), tapeworms, and flukes (only adults). Most other benzimidazoles are not effective against flukes, and the oldest ones are also ineffective against tapeworms. Albendazole also kills eggs of roundworms and flukes (ovicidal activity). All this made albendazole particularly popular for use on livestock. As other benzimidazolesalbendazole has no efficacy whatsoever against external parasites (ticksflies, lice, mites, etc).

A significant disadvantage of albendazole is that it can be teratogenic (other benzimidazoles too, e.g. ricobendazole, parbendazole and cambendazole), i.e. it can cause malformations in the embryos and therefore should not be administered to pregnant animals. Albendazole is abundantly used worldwide in numberless generic brands for livestock, but significantly less for pets. It is not used in agriculture.

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.