21 CFR § 520.1802a - Piperazine-carbon disulfide complex suspension.

---
identifier: "/us/cfr/t21/s520.1802a"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 520.1802a - Piperazine-carbon disulfide complex suspension."
title_number: 21
title_name: "Food and Drugs"
section_number: "520.1802a"
section_name: "Piperazine-carbon disulfide complex suspension."
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"
---


# 520.1802a Piperazine-carbon disulfide complex suspension.

(a) *Specifications.* Each fluid ounce of suspension contains 7.5 grams of piperazine-carbon disulfide complex. The piperazine-carbon disulfide complex contains equimolar parts of piperazine and carbon disulfide (1 gram contains 530 mgs of piperazine and 470 mgs of carbon disulfide).

(b) *Sponsor.* See No. 054771 in § 510.600(c) of this chapter.

(c) *Conditions of use in horses and ponies*—(1) *Amount.* Administer 1 fluid ounce per 100 pounds of body weight by stomach tube or dose syringe after withholding feed overnight or for 8 to 10 hours.

(2) *Indications for use.* For removing ascarids (large roundworms, *Parascaris equorum),* bots (*Gastrophilus* spp.), small strongyles, large strongyles (*Strongyles* spp.), 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.

[45 FR 52781, Aug. 8, 1980, as amended at 78 FR 28826, May 20, 2014]