Brand: CYDECTIN ® 1% w/v S Injection for Cattle & Sheep


FORMULATION: «injectable» to be administered subcutaneously in the anterior half of the neck.

ACTIVE INGREDIENT(S): moxidectin: 10 mg/mL (=1.0%)

CHEMICAL CLASS of the active ingredient(s): macrocyclic lactone


CATTLE & HEEP (cattle everywhere, sheep in some countries)

PARASITES CONTROLLED* (spectrum of activity)

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




*Can be slightly different in some countries: read the product label!

  • Cattle: 200 mcg/kg bw, equivalent to 1 ml/50 kg (= 110 lb) bw
  • Sheep: 200 mcg/kg bw, equivalent to 0.1 ml/5 kg (= 11 lb) bw


  • LD50 (acute oral) in rats: 106 mg/kg (for the a.i., source MSDS)
  • LD50 (acute dermal) in rats: >2000 mg/kg (for the a.i., source MSDS)
  • Estimated hazard class according to the WHO: not applicable for veterinary medicines

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

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

    • Meat: USA 21; Canada 36; UK 65; Australia 14; New Zealand 35.
    • Milk: Not approved in most countries.
    • UK 70; New Zealand 28.
    • Milk: Not approved in most countries.

The different withholding periods in various countries illustrate the fact that unfortunately, national regulatory authorities often draw different conclusions from the same scientific evidence. This has been always so and there are no indications that things will improve in the near future.

WARNING !!!: Never use on humans, dogs or cats


Risk of resistance? YES, in gastrointestinal roundworms in sheep (very high), goats (very high) particularly in:

Resistance of gastrointestinal roundworms to macrocyclic lactones in sheep, goats and cattle has been reported in numerous countries. Most cases have been reported for ivermectin, and moxidectin often works well against ivermectin-resistant worms initially. But if moxidectin use continues gastrointestinal roundworms will become resistant to it rather quickly. Based on the very abundant and frequent use of ivermectin and other macrocyclic lactones in livestock (with more-or-less cross-resistance to ivermectin) it must be assumed that resistance of gastrointestinal roundworms to this chemical class will continue spreading and strengthening in the future.

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:

These alternative products may not be available in all countries, or may not be available as injectables.

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: Worldwide, including the US, Canada, the EU, Australia, etc. Marketing of the CYDECTIN (and other moxidectin formulations) is quite special. It is marketed by ZOETIS in the UK (and other EU countries) and New Zealand; by BOEHRINGER INGELHEIM in the USA and Canada; by VIRBAC in Australia, etc. Moxidectin, the a.i. of CYDECTIN was introduced by AMERICAN CYANAMID in the 1990s. After various subsequent acquisitions it landed in FORT DODGE, a part of WYETH, which was acquired by PFIZER. But PFIZER Animal Health already had its own livestock ML (doramectin), and two livestock MLs were obviously redundant. After their spin-off from PFIZER, ZOETIS has reasonably decided to get rid of CYDECTIN, at least partially and has sold or licensed it out to several companies. The current situation may change in the future.
GENERIC BRANDS available? YES, many brands in some countries (e.g. Australia), rather few, if at all, in other countries (e.g. the EU, USA). It happens that many Animal Health companies without an own macrocyclic lactone (ML) for livestock prefer generic ivermectin instead of moxidectin or other MLs. A simple reason is that ivermectin was the first ML that lost patent protection and became available in the generics market. Another one is that the offer of generic ivermectin is much higher and thus prices lower than for moxidectin or other MLs (e.g. doramectin, eprinomectin, etc.). Although moxidectin may have some advantages over ivermectin in particular markets (e.g. sheep scab control), ivermectin is often good enough for most indications.

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

For an overview on the most used antiparasitic injectable brands for livestock click here.


CYDECTIN injection for cattle & sheep was the first formulation of moxidectin (1%) launched by AMERICAN CYANAMID in the mid 1990s. After the tremendous success of ivermectin in the 1980s, all multinational Animal Health companies concentrated their efforts on discovering their own macrocyclic lactone comparable to ivermectin. AMERICAN CYANAMID was one of the few companies that made it (which was not enough to ensure it's survival...).

Moxidectin is a macrocyclic lactone introduced in the 1990s (by AMERICAN CYANAMID). It is moderately used in livestock and pets, but not in agriculture. Its spectrum of activity is similar to the one of  ivermectin, i.e. basically roundworms and certain external parasites (mites, lice, etc.). As all other macrocyclic lactones moxidectin is not effective against tapeworms and flukes. Moxidectin is generally considered as more potent than ivermectin against gastrointestinal nematodes of livestock, particularly in sheep and goats, and against a few other livestock pests (e.g. sheep scab, cattle ticks, etc.). It is also less toxic than ivermectin, which makes it possible to use it at higher rates, particularly in long-acting formulations. Moxidectin is moderately used in livestock and horses, but rather scarcely in pets. It is not used in agriculture.

There are other formulations for topical (pour-on) and oral (drench) administration, mainly for cattle and/or sheep. So far there are no moxidectin products for use on swine.

The different withholding periods in various countries illustrate the fact that unfortunately, national regulatory authorities often draw different conclusions from the same scientific evidence. This has been always so and there are no indications that things will improve in the near future.

Being an excellent antiparasitic, comparable to ivermectinmoxidectin does not control all parasites of livestock. Unfortunately advertising and even the label of some generic formulations in less developed countries often include unsubstantiated claims. To help preventing confusion and misuse it is useful to know that whatever moxidectin 1% injectable used at the recommended dose DOES NOT CONTROL:

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.