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: "520.1326b"
section_subject: "Mebendazole and trichlorfon paste."
cfr_reference: "21 CFR 520.1326b"
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 gram of paste contains 100 milligrams of mebendazole and 454 milligrams of trichlorfon.
(b)Sponsor. See No. 000061 in § 510.600(c) of this chapter.
(c)Conditions of use in horses—(1) Amount. 8.8 milligrams of mebendazole and 40 milligrams of trichlorfon per kilogram of body weight.
(2)Indications for use. It is used in horses for treatment of infections of bots (Gastrophilus intestinalis and G. nasalis), large roundworms (Parascaris equorum), large strongyles (Strongylus edentatus, S. equinus, S. vulgaris), small strongyles, and pinworms (Oxyuris equi).
(3)Limitations. Do not administer more than once every 30 days. Do not treat sick or debilitated animals, foals under 4 months of age, or mares in the last month of pregnancy. Trichlorfon is a cholinesterase inhibitor. Do not administer simultaneously or within a few days before or after treatment with, or exposure to, cholinesterase-inhibiting drugs, pesticides, or chemicals. Do not administer intravenous anesthetics, especially muscle relaxants, concurrently. Not for use in horses intended for food. Consult your veterinarian for assistance in the diagnosis, treatment, and control of parasitism.