Company: BAYER

FORMULATION: «injectable» to be administered subcutaneously under the loose skin in front of, or behind, the shoulder in cattle; in the neck in sheep; immediately behind the ear in swine.

ACTIVE INGREDIENT(S): ivermectin: 5 mg/mL (=0.5%)

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



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
  • Swine: 300 mcg/kg bw, equivalent to 1 ml/33 kg


  • LD50 (acute oral) in rats: 300 to 2000 mg/kg (estimate in the MSDS)
  • LD50 (acute dermal) in rats: >5000 (estimate in the MSDS)
  • Estimated hazard class according to the WHO: not applicable for veterinary medicines

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

Withholding period for meat (country-specific differences may apply: read the product label)

  • Cattle: AUS: 28 days; NZL: 49 days
  • Swine: AUS: 28 days

Not approved for use on dairy cows producing milk for human consumption.

Non-lactating dairy cattle: treat at least 28 days months prior to calving.

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


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

Resistance of gastrointestinal roundworms to ivermectin in sheep, goats and cattle has been reported almost worldwide, including the USA, UK, Australia and New Zealand. Based on the very abundant and frequent use of ivermectin and other macrocyclic lactones (with cross-resistance to ivermectin) in livestock it must be assumed that resistance of these 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 gastroinitestinal roundworms through product rotation:

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

Resistance of cattle ticks Rhipicephalus (Boophilus) microplus to ivermectin has been reported in several Latin American countries. It is not yet a widespread problem, but nevertheless a warning. Based on the intensive use of macrocyclic lactones on cattle it is only a matter of time for resistance of cattle ticks to these compounds to develop elsewhere unless specific resistance preventative meaures (e.g. rotation, IPM, etc.) are taken.

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 product is marketed (maybe under another TM): Australia. In New Zealand (only for cattle) and other countries under the brand BAYMEC
GENERIC BRANDS available? YES, worldwide by the hundreds. Ivermectin 1% injectable is probably the veterinary product with more generic brands worldwide.

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

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


BOMECTIN = BAYMEC 1% injectable are two of the numberless generic brands of the ivermectin 1% injectable formulation, in this case from BAYER.

There are also numerous mixtures of ivermectin with other active ingredients, as well as other formulations for topical (pour-on) and oral (drench, feed additives) administration.

Whereas this type of ivermectin 1% injectables are approved for use on cattle worldwide, approval for use on sheep, swine & goats depends on the country. These differences are most likely due to marketing strategies of the different companies (e.g. market segmentation, local product portfolio, etc.) and not to regulatory hurdles.

Unfortunately, withholding periods for meat of the ivermectin 1% injectable vary considerably in different countries. This illustrates the fact that national regulatory authorities often draw different conclusions from exactly the same scientific evidence. This has been always so and there are no indications that things will improve in the near future.

All 1% ivermectin injectables used on cattle at the recommended dose of 200 mcg/kg offer a rather poor control of cattle ticks Boophilus (=Rhipicephalus) microplus, usually insufficient for most producers.

Being one of the best antiparasitics ever developed, ivermectin 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 ivermectin 1% injectable used at the recommended dose DOES NOT CONTROL:


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.

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