Zilmax^® Information Center

The following information is in response to recent questions about Zilmax®. It is intended for our customers and interested groups who are involved in animal husbandry and well-being.

The benefits and safety of Zilmax® (zilpaterol hydrochloride) are well documented and the product has a 30+ year history of research and development and rigorous testing. Worldwide regulatory agencies have reviewed extensive data on Zilmax and have concluded that use of Zilmax, according to the label, is safe in cattle. It is important to understand these data included rigorous animal health safety and well-being studies – conducted by university experts – that found the behavior and movement of cattle fed Zilmax is normal.

Zilmax has a withdrawal period of 3 days prior to harvest. Not for use in animals intended for breeding. Do not allow horses or other equines access to feed containing zilpaterol. Do not use in veal calves. Not to be fed to cattle in excess of 90 mg/head/day in complete feed. If pen consumption of complete feed exceeds 26.5 lb/head/day (90 percent dry matter basis), zilpaterol should not be fed in complete feed. For complete information, refer to the product label.

More Information

• Certification Program
• Best Management Practices Program
• Zilmax Sustainability Benefits Infographic
• Animal Safety & Well-being Fact Sheet
• Fatigue Cattle Syndrome Fact Sheet
• Research: “Description of a novel fatigue syndrome of finished feedlot cattle following transportation” (July 1, 2015)
• Research: “Effect of ractopamine hydrochloride and zilpaterol hydrochloride on cardiac electrophysiologic and hematologic variables in finishing steers” (September 15, 2016)
• FAQs about Zilmax
• Product Label(s) and MSDS (U.S)

Related Websites

• Zilmax.com
• Information for U.S. cattle owners: ResponsibleBeef.com
• For more information about beta-agonists: FactsAboutBeef.com

Press Releases and Statements

• Merck Animal Health Provides Update on Zilmax Five-Step Plan, Announces Next Steps (November 5, 2014)
• Merck Animal Health Shares Progress on Zilmax and the Five-Step Plan for Responsible Beef (December 2013)
• Five-Step Plan Update: Merck Animal Health Advisory Board (October 2013)
• Merck Animal Health Strengthens Commitment to Five Steps to Responsible Beef (August 16, 2013)
• Merck Animal Health Statement on Five Steps to Responsible Beef (August 13, 2013)
• Merck Animal Health Statement on Zilmax (August 8, 2013)
• Merck Animal Health Statement on Animal Safety and Well-being Studies (August 8, 2013)