21 CFR § 520.1855 - Ponazuril.

---
identifier: "/us/cfr/t21/s520.1855"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 520.1855 - Ponazuril."
title_number: 21
title_name: "Food and Drugs"
section_number: "520.1855"
section_name: "Ponazuril."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "E"
subchapter_name: "ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS"
part_number: "520"
part_name: "ORAL DOSAGE FORM NEW ANIMAL DRUGS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 360b."
regulatory_source: "40 FR 13838, Mar. 27, 1975, unless otherwise noted."
cfr_part: "520"
---


# 520.1855 Ponazuril.

(a) *Specifications.* Each gram of paste contains 150 milligrams (mg) ponazuril.

(b) *Sponsor.* See No. 000010 in § 510.600(c) of this chapter.

(c) *Conditions of use in horses*—(1) *Amount.* Administer orally 15 mg per kilogram (kg) (6.81 mg per pound (lb)) body weight as the first dose, followed by 5 mg/kg (2.27 mg/lb) body weight once daily for a period of 27 additional days.

(2) *Indications for use.* For the treatment of equine protozoal myeloencephalitis caused by *Sarcocystis neurona.*

(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.

[66 FR 43774, Aug. 21, 2001, as amended at 79 FR 28827, May 20, 2014; 80 FR 34278, June 16, 2015; 80 FR 53459, Sept. 4, 2015; 84 FR 39183, Aug. 9, 2019]