Dear Veterinarian Letter regarding use of aspirin products in lactating dairy cattle

Dear Veterinarian:

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. The extralabel use of unapproved drugs in food-producing species is prohibited. 

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. 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).

Under the Animal Medicinal Drug Use Clarification Act (also known as AMDUCA), veterinarians may use an FDA-approved human or animal drug in food-producing species under specific conditions. There is one FDA-approved human aspirin product (Vazalore) that is currently marketed. Although other human aspirin products are marketed under an over-the-counter monograph, that monograph is not an approval and, therefore, these products cannot be used in an extralabel manner. Given the impracticality of dosing cattle with a sufficient amount of the approved human product, the FDA understands that veterinarians and dairy farmers may instead be using unapproved aspirin products that are not legally marketed. The extralabel use of unapproved drug products in food-producing species is prohibited. 

Veterinarians and dairy farmers should stop use of unapproved aspirin in lactating dairy cattle and use FDA-approved products to control pyrexia and pain. In the event that animals have already been treated with aspirin, veterinarians should use their scientific expertise and available resources to set protective and extended milk and meat withdrawal periods for treated animals.