subchapter_subject: "ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS"
part_code: "520"
part_subject: "ORAL DOSAGE FORM NEW ANIMAL DRUGS"
subpart_code: "B"
subpart_subject: "Specific Administrative Rulings and Decisions"
section_number: "520.2520b"
section_subject: "Trichlorfon boluses."
cfr_reference: "21 CFR 520.2520b"
title_name: "Title 21"
title_subject: "Food and Drugs"
parts_covered: "Parts 500 to 599"
revised_date: "Revised as of April 1, 2019"
publication_date: "As of April 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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(a)Specifications. Each bolus contains either 7.3, 10.9, 14.6, or 18.2 g of trichlorfon.
(b)Sponsor. See No. 054771 in § 510.600(c) of this chapter.
(c)Conditions of use in horses—(1) Amount. 18.2 milligrams per pound of body weight, except for strongyles use 36.4 milligrams per pound of body weight.
(2)Indications for use. For horses for removal of bots (Gastrophilus nasalis, Gastrophilus intestinalis), large strongyles (Strongylus vulgaris), small strongyles, large roundworms (ascarids, Parascaris equorum), and pinworms (Oxyuris equi).
(3)Limitations. Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian.