Brand: AVENGE ™ Pour-on Lousicide for Sheep


FORMULATION: «pour-on» for topical administration as a single strip along the backline.

ACTIVE INGREDIENT(S): Imidacloprid: 3.5% = 35 g/L

CHEMICAL CLASS of the active ingredient(s): neonicotinoid


PARASITES CONTROLLED (spectrum of activity)

  • Sheep body lice Bovicola (Damalinia) ovis, on shorn sheep up to 7 days off shears and unshorn lambs up to 2 months of age


Sheep weight (kg) Dose rate (mL)
Up to 30 kg: One strip
< 6 8
6.0 - 8.0 12
8.1 - 10.0 15
10.1 - 12.5 20
12.6 - 15 25
15.1 - 20 30
20.1 - 30 40
Over 30 kg: Two strips
30.1 - 55 40
55.1 - 80 80
80.1 - 100 90


  • LD50 (acute oral) in rats: >5000 mg/kg (according to MSDS)
  • LD50 (acute dermal) in rats: >2000 mg/kg (according to MSDS)
  • Estimated hazard class according to the WHO: U = Unlikely to present acute hazard in normal use.

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

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

  • Meat: 21 days (ESI 63 days).
  • Wool: 6 months.
  • Milk for human consumption: Do not use on female sheep which are producing, or may in the future produce, milk or milk products for human consumption.

Imidacloprid and other neonicotinoids have been associated with bee colony collapse worldwide. In April 2013 the EU prohibited for two years the use of several neonicotinoids on various crops due to suspected detrimental effects on bee colonies. However there is so far no evidence that use on sheep may have a detrimental effect on bees.

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? LOW, in sheep body lice.

This means that if this product does not achieve the expected efficacy against the mentioned parasites, it is likely to be due to incorrect use and not to resistance. Incorrect use is the most frequent cause of product failure.

Imidacloprid, a neonicotinoid insecticide was introduced for body lice control of sheep in Australia around 2010. So far there are no reports on resistance or tolerance of body lice to imidacloprid in Australia or elsewhere. However, other pests have already developed resistance to imidacloprid and other neonicotinoids (e.g. houseflies) in several countries. And in the past, body lice have developed resistance to several classes of insecticides (e.g. synthetic pyrethroids, benzoylphenyl ureas) in Australia. Consequently it must be assumed that they will sooner or later develop resistance to imidacloprid as well, particularly if it is uninterruptedly used for years. To delay resistance development Integrated Pest Management (IPM) practices are a must, including product rotation with with lousicides showing mechanisms of action different from that of imidacloprid.

Alternative chemical classes/active ingredients to prevent resistance of external parasites through product rotation:

These alternative products may not be available in all countries, or may not be available as pour-ons.

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
GENERIC BRANDS available? Yes

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

For an overview on the most used antiparasitic pour-on brands click here.


AVENGE Pour-on Lousicide for Sheep from BAYER (now ELANCO) was the first product containing imidacloprid approved for use on livestock in Australia. There are no products containing imidacloprid approved for livestock in the USA and in the EU. Although imidacloprid seems theoretically a suitable candidate for controlling flies and other insects that affect livestock, BAYER waited about 20 years before introducing such products for livestock after it was introduced for pets in the 1990's, for whatever reasons. After patent expiry some local companies in Latin America have introduced several pour-ons with generic imidacloprid for fly control on cattle.

Imidacloprid, a neonicotinoid insecticide was introduced by BAYER in the early 1990s and is massively used in pesticides for crop protection and for the control of public and household pests (cockroaches, termites, etc.). It is also vastly used in dogs and cats for flea control. As most other neonicotinoids it is a non-systemic contact insecticide, effective against a number of insect pests such as lice, fleas and flies. It has no acaricidal efficacy, i.e. it does not affect ticks or mites. It has no effect whatsoever on internal parasites (roundworms, tapeworms, flukes, etc.).


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.