The increased use of aspirin (acetylsalicylic acid) to treat pyrexia and pain in dairy cattle infected with highly pathogenic avian influenza (HPAI) H5N1 prompted FDA to issue a warning to producers and veterinarians in October. Previously, FDA had stated that aspirin use was of low regulatory concern. However, due to its increased use because of H5N1, FDA has shifted its stance.
“The U.S. Food and Drug Administration understands that veterinarians and dairy farmers may be treating lactating dairy cattle for pyrexia and pain with aspirin and wants to clarify that there are no FDA-approved aspirin products for use in cattle,” FDA said in a letter to veterinarians. “There are FDA-approved products for controlling pyrexia and pain in lactating dairy cattle that are safe, effective, and have established milk and meat withdrawal periods.”
How Does This Affect the U.S. Swine Industry?
The same regulations that guide the use of aspirin in dairy cattle also guide its use in swine, reminded Locke Karriker, DVM, professor at Iowa State University College of Veterinary Medicine and American Association of Swine Veterinarians (AASV) president-elect, in a recent Swine Health Information Center/AASV webinar.
“Currently, those regulations mean that there is no legal pathway to use aspirin in swine and it should be avoided,” Karriker says.
Under the Animal Medicinal Drug Use Clarification Act (AMDUCA), veterinarians may use only FDA-approved human or animal drug in food-producing species under specific conditions in an extra-label manner. The extra-label use of unapproved drugs in food-producing species is prohibited.
All FDA-approved animal products are required to carry one of the following statements on the label:
“Approved by FDA under NADA # XXX-XXX” (for brand name animal drugs), or
“Approved by FDA under ANADA # XXX-XXX” (for generic animal drugs).
With no legal pathway to use true aspirin in swine, experts are looking into other potential treatments and other nonsteroidals and how they may be evaluated.
“The industry, veterinarians and university-based clinical scientists are working to develop alternatives to aspirin use while exploring the development of products that contain aspirin and conform to regulatory requirements,” Karriker says. “This includes cooperation among the professional veterinary organizations for bovine, poultry and swine medicine as well as dialog with the FDA directly.”
Dusty Oedekoven, DVM, chief veterinarian for the National Pork Board, says this situation is a good example why involvement of a licensed, accredited veterinarian is important in providing timely care for animals while ensuring regulatory compliance and food safety.
“My recommendation to producers is to consult with your herd veterinarian regarding the use of any animal health products, including aspirin products (acetylsalicylic acid),” Oedekoven says.
Karriker adds that depending on the case context and clinical signs, there may be several options that do have a legal status.
Learn more here from this list of resources compiled by AASV:
FDA AMDUCA website — Resource information from the FDA regarding AMDUCA.
AMDUCA and Extra-label Drug Use in Swine — A brochure providing an algorithm for the use of drugs in an extra-label manner and describing additional restrictions for the extra-label use of cephalosporins and fluoroquinolones.
AVMA: Extralabel Drug Use (ELDU) Algorithm — An online algorithm.
AMDUCA Revisited — JSHAP article describing AMDUCA in swine medicine.
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