Drugs in Animal Food (Medicated Feeds)
Anyone who adds drugs to animal food creates medicated feeds and as such is subject to the Federal Food, Drug and Cosmetic Act (the Act). Just as each label claim for a new animal drug must be approved, a drug must be specifically approved for use in or on animal food. When the new animal drug application for use of the drug in or on animal food is approved, a notice is published in the Federal Register. The medicated feed must be labeled in accordance with the approved representative labeling.
A drug may only be mixed into feed for uses and at drug levels specifically permitted by approvals and listed in the regulations (21 CFR Part 558.) The person or firm mixing a medicated feed from a Category II, Type A medicated article or liquid and free-choice feed, using either Category II or Category I, Type A medicated articles that must follow proprietary formulas or specifications (21 CFR Part 558.4) must be registered with the FDA as a drug manufacturer and hold an approved medicated feed mill license.
It is a violation of the Act for drugs to be added to animal food for uses or at levels not specified in the approvals. Any individual authorizing the violation, as well as the individual illegally mixing the medicated feed may be subject to regulatory action. Additionally, the feed itself may be subject to seizure. The agency is unlikely to consider taking a regulatory action when it encounters an extra-label use of medicated feed in minor species provided certain conditions are met, including the involvement of a licensed veterinarian.
Veterinary Feed Directives
The Animal Drug Availability Act of 1996 (ADAA) amended the Act to establish a new class of drugs, veterinary feed directive (VFD) drugs. A drug approved for use in or on animal food as a VFD drug can be fed to animals only under the professional supervision of a licensed veterinarian. The first final rule covering the use and distribution of VFD feeds (medicated feeds containing VFD drugs) was published in the Federal Register on December 8, 2000. The second, and current, VFD rule was published on June 3, 2015.
The VFD process is straightforward in practice. A veterinarian, operating within the confines of a valid veterinarian-client-patient relationship, examines and diagnoses animal conditions and determines whether a condition warrants use of a VFD drug. If it does, the veterinarian will issue a signed VFD order containing information specified by regulation. Like with any other drugs used in or on animal feed, extra-label use of a VFD drug is not permitted. The appropriate statement to that effect is required to appear on every VFD order. The veterinarian completes and signs the VFD order, keeps the original and provides one copy to the client and another to the distributor. All three parties, the veterinarian, the client, and the distributor are required to keep the VFD order in their files for 2 years from the date of issuance. The VFD order allows the VFD feed to be issued to the client for feeding to the animals specified on the VFD.
Anyone intending to distribute VFD feeds must notify CVM prior to beginning distribution. Distributor includes the VFD feed manufacturer or anyone in the distribution chain who ultimately supplies VFD feed to an animal producer upon receiving a valid VFD order. The veterinarian could be a distributor of VFD feed. A VFD feed may not be fed without a signed, valid VFD. However, VFD feed may be sent down the distribution chain if the consignee, i.e., another distributor, provides the distributor with a signed acknowledgment letter affirming that it will only issue the VFD feed to a client upon receiving a valid VFD order holder or to another distributor upon receiving the acknowledgment letter.