Virginiamycin is an antibiotic of the streptogramin class that has been used in animal feeds to prevent disease and improve growth. Veterinarians prescribe virginiamycin to prevent necrotic enteritis in chickens and to treat laminitis in horses.

Virginiamycin review

Status: review completed

The APVMA reviewed the use of virginiamycin in food-producing animals because of concerns that using virginiamycin for growth promotion could pose an undue risk to human health. Given the use patterns of virginiamycin in intensive animal farming practices in Australia, there were concerns about the spread of resistant animal bacteria to humans and the transfer of antibiotic resistant genes from animal bacteria to human pathogens.

The review did not include the use of virginiamycin in horses, as they are not considered to be a food-producing species in Australia.

In November 2004 the APVMA released its decision on the review of virginiamycin. The APVMA decided to vary the labels of Eskalin Feed Premix for Cattle (APVMA 46049), Eskalin Wettable Powder Spray-On Feed Premix (APVMA 49111) and Eskalin 500 Feed Premix (APVMA 51354) by imposing mandatory restrictions on off-label uses, limiting the duration of use of the products to 28 days, and limiting the number of re-treatments of virginiamycin in a 12-month period. In 2005, Phibro Animal Health, the registrant of the three affected products, applied to the Administrative Appeals Tribunal (AAT) for a review of APVMA's decision.

During the AAT proceedings, Phibro Animal Health and the APVMA agreed that virginiamycin could be used prudently. The AAT determined that the label changes above would not proceed. Instead, the labels would be varied to require that veterinarians will prescribe the three Eskalin products in accordance with the Australian Veterinary Association's Code of Practice for Prescription and Use of Products Which Contain Antimicrobial Agents. This Code of Practice contains specific guidelines for the use of products that contain virginiamycin.

Labels for products that contain virginiamycin now bear the following mandatory prudent use statements:

Prior to prescribing [Name of Product] investigate the use of non-antibiotic options. If virginiamycin is indicated and selected for use, prescription must be consistent with the AVA Code of Practice (external site) for Prescription and Use of Products which Contain Antimicrobial Agents. Dosage regimens should be designed for each situation with an appropriate duration and frequency to minimise treatment failure while minimising the emergence of antimicrobial resistance. Review farm records on the use of product containing virginiamycin to ensure compliance with prescribing instructions.


More Information

Virginiamycin review archive

Title Date
Virginiamycin Final Report (PDF, 378kb) Nov 2004
Preliminary Review Findings Report ( PDF, 430kb) Apr 2003
Gazette Notice: APVMA reaches the conclusion of the review of virginiamycin Apr 2005
Media Release: Regulatory changes for veterinary antibiotic Nov 2004


For more information contact:

Chemical Review

Phone: +61 2 6210 4749

Fax: +61 2 6210 4776


Product Search

Search the PUBCRIS database for registered products that contain virginiamycin.

Last updated on 23 April, 2012

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