On Oct. 22, 1994, the Animal Medicinal Drug Use Clarification Act (AMDUCA) became law permitting veterinarians to prescribe extralabel uses of certain approved new animal drugs and approved human drugs for animals under certain conditions.

Extralabel use refers to the use of an approved drug in a manner that is not in accordance with the approved label directions. Under the AMDUCA provisions, FDA has the right to prohibit extralabel uses of certain drugs in animals.