{"data":{"id":"us/21-cfr-558.582","jurisdiction":"us","citation":"21 CFR 558.582","heading":"Sulfamerazine.","body":"(a) Specifications. Type A medicated articles containing 99 percent sulfamerazine.\n(b) Sponsor. See No. 054771 in § 510.600(c) of this chapter.\n(c) Related tolerances. See § 556.660 of this chapter.\n(d) Special considerations. (1) Federal law restricts medicated feed containing this veterinary feed directive (VFD) drug to use by or on the order of a licensed veterinarian. See § 558.6 for additional requirements.\n(2) The expiration date of VFDs for sulfamerazine medicated feeds must not exceed 6 months from the date of issuance. VFDs for sulfamerazine shall not be refilled.\n(e) Conditions of use. It is used in fish feed for as follows:\nSulfamerazine grams/ton Combination in grams/ton Indications for use Limitations Sponsor\n(1) To deliver 10 grams of sulfamerazine per 100 pounds of fish per day Rainbow trout, brook trout, and brown trout: For control of furunculosis Formulate to deliver 10 grams of sulfamerazine per 100 pounds of fish per day. Treat for not more than 14 days. Do not treat within 3 weeks of marketing or stocking in stream open to fishing 054771\n(2) [Reserved]","path":["Title 21—Food and Drugs","CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES","SUBCHAPTER E—ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS","PART 558—NEW ANIMAL DRUGS FOR USE IN ANIMAL FEEDS","Subpart B—Specific New Animal Drugs for Use in Animal Feeds"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-21.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:47Z","sha256":"71423aae709b5e3a2b4e4fd64137248479fff16d69bd0e9c217feb4ba03b2c09","source_id":"us-cfr","stale":true,"prev":"us/21-cfr-558.575","next":"us/21-cfr-558.586"},"notice":"GroundRules: Original legal text. Not legal advice."}