Animal & Veterinary
FDA Prohibits Nitrofuran Drug Use
FDA Veterinarian Newsletter 2002 Volume XVII, No II
FDA is issuing an order prohibiting the extralabel use of topical nitrofuran animal and human drugs in food-producing animals. This order is based on evidence that extralabel use of topical nitrofuran drugs in food-producing animals may result in the presence of residues that are carcinogenic and have not been shown to be safe. The Agency finds that such extralabel use presents a risk to the public health for the purposes of the Animal Medicinal Drug Use Clarification Act (AMDUCA) of 1994.
AMDUCA amended the Federal Food, Drug, and Cosmetic Act to allow licensed veterinarians to prescribe extra-label uses of approved animal drugs and human drugs in animals. Section 2(a)(4)(D) of the AMDUCA provides that the Agency may prohibit an extra-label drug use in animals if, after affording an opportunity for public comment, the Agency finds that such use presents a risk to the public health.
In the past, FDA permitted two approved topical nitrofurans to be used in cattle. These products were:
- Furazolidone aerosol powder (trade names such as Topazone and Furox aerosol.)
- Nitrofurazone topical powder for pinkeye and wounds (trade names such as NFZ Puffer and P.E. 7.)
A carbon-14 (C-14) radio-label residue depletion study conducted by the FDA showed that detectable levels of nitrofuran derivatives are present in edible tissues (milk, meat, kidney, liver) of cattle treated by the ocular (eye) route. The study indicates that use of these nitrofuran products may pose a risk to public health because residues of known carcinogens are present in edible tissues.
The current list of prohibited drugs includes furazolidone and nitrofurazone, but it contains the parenthetical statement (except for approved topical use). FDA plans to remove this parenthetical statement. Once this prohibition is in place, the revised list will state that the following drugs (both animal and human), families of drugs, and substances are prohibited for extra-label uses in all food-producing animals.
- Diethylstilbestrol (DES);
- Other nitroimidazoles;
- Furazolidone, Nitrofurazone, other nitrofurans;
- Sulfonamide drugs in lactating dairy cattle (except approved use of sulfadimethoxine, sulfabromomethazine, and sulfaethoxypyridazine);
- Fluoroquinolones; and
FDA will consider all comments on this order that the Agency receives by April 8, 2002. Written comments should be submitted to the Dockets Management Branch (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Room 1061, Rockville, MD 20852. Electronic comments may be submitted to http://www.accessdata. fda.gov/scripts/oc/dockets/commentdocket.cfm. All comments should include Docket number 01N-0499. The order will become effective May 7, 2002, unless FDA revokes or modifies the order or extends the comment period.
Additional information on this prohibition is contained in the February 6, 2002, Federal Register (). Questions about this prohibition may be directed to: Gloria J. Dunnavan, Center for Veterinary Medicine (HFV-230), Food and Drug Administration, 7500 Standish Place, Rockville, MD 20855, 301-827-1168, e-mail: gdunnava@ cvm.fda.gov . Please note that the address and telephone number for Ms. Dunnavan in the February 6, 2002, Federal Register is incorrect.