Use of the food animal residue avoidance databank

In its extra-label drug use policy, the FDA states, as one of the criteria for permitting extra-label drug use, that a significantly extended time period be assigned for drug withdrawal prior to marketing meat, milk or eggs. The phrase "significantly extended time period" is taken to mean, at minimum, the amount of time necessary for any drug residues to deplete to subtolerance levels; however, determination of this period is left to the discretion of the veterinarian responsible for the extra-label drug use. The extended period will vary for each drug, dose, species, and route of administration. Therefore, it is unrealistic to assume that the practitioner can make a rational determination of extended drug withdrawal times without more information than is available through textbooks and professional journals. FARAD was specifically designed to provide veterinarians with the information required to determine extended withdrawal times, and thus prevent residues when drugs are used in an extra-label manner. FARAD can provide valuable residue avoidance assistance to veterinarians when drugs are administered in an extra-label manner, but it is not the answer to the national drug residue problem. Most residues result from failure to observe label-recommended withdrawal times, whereas less than 20% are thought to result from extra-label drug use. A substantial armamentarium of approved drugs is available to the veterinarian to treat most diseases in beef cattle, swine, and broiler chickens; thus, extra-label drug use in these species is unnecessary under most conditions.(ABSTRACT TRUNCATED AT 250 WORDS)