21 U.S.C. § 354 — Veterinary feed directive drugs

(a) Lawful veterinary feed directive requirement. (1) A drug meant for use in animal feed that's approved — or conditionally approved, or listed on an index — only for use under a licensed veterinarian's supervision is called a "veterinary feed directive drug." Feed containing it may only be fed to animals under a lawful directive written by a licensed veterinarian acting within their normal professional practice. When the drug and the feed containing it are labeled, distributed, held, and used according to this section, they're excused from the general misbranding rule in section 352(f). (2) A directive is lawful if it (A) contains whatever information the Secretary requires by regulation or order, and (B) matches the approved conditions and uses for the drug published under section 360b(i), or the index listing under section 360ccc–1(e). (3)(A) Everyone involved in distributing or using the feed, and the veterinarian who wrote the directive, must keep a copy of it for each feed — except a person who distributes the feed on to someone else for further distribution. That person must instead keep a written acknowledgment from the receiver promising not to ship the feed to a farm without a valid directive, and not to ship it on to anyone else unless that person gives the same written promise to their own supplier. (B) Anyone required to keep these records, and anyone in charge of them, must let an officer or employee the Secretary designates inspect, copy, and verify the records at reasonable times, on request. (C) Anyone who starts distributing this kind of feed must notify the Secretary of their name and business address. Failing to give that notice makes the drug misbranded. (b) Labeling and advertising. The drug and any feed containing it are treated as misbranded if their label lacks the warning statements and other information the Secretary requires by regulation or order, or if their advertising doesn't match the approved conditions and uses published under section 360b(i) or the index listing under section 360ccc–1(e), or lacks the general warning statement the Secretary prescribes. (c) Nonprescription status. Even though it requires a veterinarian's authorization, this drug — and any animal feed containing it — is not treated as a prescription drug under any federal or state law.