{"data":{"id":"us/21-cfr-520.1638","jurisdiction":"us","citation":"21 CFR 520.1638","heading":"Oxibendazole.","body":"(a) Specifications. (1) Each gram of paste contains 227 milligrams (mg) (22.7 percent) oxibendazole.\n(2) Each milliliter of suspension contains 100 mg (10 percent) oxibendazole.\n(b) Sponsor. See No. 054771 in § 510.600(c) of this chapter.\n(c) Special considerations. (1) See § 500.25 of this chapter.\n(2) Suspension product described in paragraph (a)(2) of this section shall be labeled: “Federal law restricts this drug to use by or on the order of a licensed veterinarian.”\n(d) Conditions of use in horses—(1) Amount. For uses other than for threadworms (Strongyloides westeri), 10 mg oxibendazole per kilogram (/kg) body weight; for threadworms (Strongyloides westeri), 15 mg/kg. Horses maintained on premises where reinfection is likely to occur should be re-treated in 6 to 8 weeks. Administer suspension product by stomach tube in 3 to 4 pints of warm water, or by top dressing or mixing into a portion of the normal grain ration.\n(2) Indications for use. For removal and control of large strongyles (Strongylus edentatus, S. equinus, S. vulgaris); small strongyles (genera Cylicostephanus, Cylicocyclus, Cyathostomum, Triodontophorus, Cylicodontophorus, and Gyalocephalus); large roundworms (Parascaris equorum); pinworms (Oxyuris equi) including various larval stages; and threadworms (Strongyloides westeri).\n(3) Limitations. Do not use in horses intended for human consumption.","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 520—ORAL DOSAGE FORM NEW ANIMAL DRUGS"],"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":"7e4dd0e558997082090913d1ec5552036c5fa77eff6c29b897239624ffeb0b3c","source_id":"us-cfr","stale":true,"prev":"us/21-cfr-520.1631","next":"us/21-cfr-520.1660"},"notice":"GroundRules: Original legal text. Not legal advice."}