Brand: EPRECIS ® 20 mg/ml solution for injection for cattle

Company: CEVA

FORMULATION: «injectable» solution to be administered subcutaneously.

ACTIVE INGREDIENT(S): eprinomectin 20 mg/mL (=2%)

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/100 kg bw


  • LD50 (acute oral) in rats: ~2750 mg/kg (estimate according to MSDS)
  • LD50 (acute dermal) in rats: >5000 mg/kg (estimate according to MSDS)
  • Estimated hazard class according to the WHO: not applicable for veterinary medicines

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

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

  • Meat: UK & EU 63 days.
  • Milk for human consumption: UK & EU: NIL.

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


Risk of resistance? YES, reported for ivermectin in gastrointestinal roundworms in cattle in several countries, particularly in the following worm species: Cooperia spp, Ostertagia spp, Haemonchus spp, Trichostrongylus spp, Oesophagostomum spp, whereby cross-resistance between eprinomectin and ivermectin must be assumed.

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 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 (maybe under another TM): UK, Ireland and EU countries
GENERIC BRANDS available? YES, but rather few and not in all countries. This brand with generic eprinomectin is marketed by CEVA in the UK and other EU countries.

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

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


EPRECIS 20 mg/mL solution for injection from CEVA is one of the so far few eprinomectin injectables for cattle, after MERIAL's LONGRANGE (5% eprinomectin injectable) not yet available everywhere.

Eprinomectin was one of the last macrocyclic lactones introduced in the 1990s (by MERIAL). It was the first macrocyclic lactone approved for use on dairy cows because it does not leave significant residues in milk, in contrast with all ivermectin-based products. Nowadays other macrocyclic lactones (e.g. doramectin, moxidectin) have been approved for use on dairy cows in some countries. The spectrum of activity of eprinomectin is similar to that of ivermectin and other macrocyclic lactones, mainly roundworms, lice and mites and, delivered as a pour-on, also some fly and tick species. It is ineffective against tapeworms and flukes. It is moderately used in cattle but not in other livestock. It is marginally used in cats, but not in dogs. It is not used in agriculture.

A long-acting injectable formulation of eprinomectin is also available for cattle (LONGRANGE, so far only in the USA), but so far neither drenches for oral administration, nor products containing mixtures of eprinomectin with other active ingredients (e.g. against liver fluke) have been introduced in most countries.

Being an excellent antiparasitic, comparable to ivermectin, eprinomectin 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 eprinomectin 0.5% pour-on formulation (without additional active ingredients) used at the recommended dose DOES NOT CONTROL:

This said, it is quite surprising that the product label for EPRECIS (solution for injection) includes an efficacy claim against adult horn flies (Haematobia irritans) and even a protection period of 7 days. To my knowledge no evidence for such efficacy of this product has been published in the scientific literature. Eprinomectin and other macrocyclic lactone pour-ons (e.g. with ivermectin or moxidectin) are also approved for adult horn fly control in most countries, but so far no injectable containing a macrocyclic lactone has got such a claim approved, not even MERIAL'S LONGRANGE injectable with 5% eprinomectin administered at 1000 mcg/kg, nor ZOETIS' CYDECTIN ONYX injectable with moxidectin 10% administered also a 1000 mcg/kg, nor MERIAL'S IVOMEC GOLD injectable with 3.15% ivermectin administered at 630 mcg/kg.

Interestingly, according to the Assessment Report issued in September 2015 by the Irish HPRA (Health Products Regulatory Authority) for the approval of this product in the EU, the efficacy claim of the APRECIS injectable against adult horn flies has been extrapolated from the pharmacokinetic data for eprinomectin (i.e. the blood levels) of the APRECIS injectable when compared with those of the original eprinomectin pour-on, EPRINEX. It seems that nobody has thought about the possibility that the efficacy of of the eprinomectin pour-on against adult horn flies may be topical, at least partially, more than systemic, i.e. caused by the active ingredient in the haircoat of treated cattle, not by the active ingredient in the blood. After topical pour-on administration the eprinomectin concentration in the hair coat of treated animals is considerable, particularly along the backline, where horn flies prefer to remain. But after injection, the concentration in the hair coat is irrelevant. In any case, no field studies on the efficacy against horn flies were presented for the EU approval of the APRECIS injectable to substantiate this claim.

Published information on the systemic efficacy of macrocyclic lactones against adult horn flies is scarce, but strongly suggests that, at the recommended eprinomectin dose of 200 mcg/kg, a significant control of adult horn flies is not to be expected, let alone a protection of 7 days against reinfestations.

For an overview and a list of the most popular antiparasitic injectables for livestock click here.


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