21 CFR § 520.2325b - Sulfaquinoxaline drench.

---
identifier: "/us/cfr/t21/s520.2325b"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 520.2325b - Sulfaquinoxaline drench."
title_number: 21
title_name: "Food and Drugs"
section_number: "520.2325b"
section_name: "Sulfaquinoxaline drench."
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"
---


# 520.2325b Sulfaquinoxaline drench.

(a) *Specifications.* A soluble powder containing 25 percent sulfaquinoxaline.

(b) *Sponsor.* See No. 016592 in § 510.600(c) of this chapter.

(c) *Related tolerances.* See § 556.685 of this chapter.

(d) *Conditions of use in cattle*—(1) *Amount.* Administer 1 teaspoon of 25 percent sulfaquinoxaline soluble powder for each 125 pounds of body weight for 3 to 5 days as a drench.

(2) *Indications for use.* For the control and treatment of outbreaks of coccidiosis in cattle and calves caused by *Eimeria bovis* or *E. zuernii.*

(3) *Limitations.* Not for use in lactating dairy cattle. A withdrawal period has not been established for this product in preruminating calves. Do not use in calves to be processed for veal. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

[79 FR 28831, May 20, 2014, as amended at 82 FR 12169, Mar. 1, 2017; 84 FR 32992, July 11, 2019; 84 FR 53310, Oct. 7, 2019]