---
kind: "section"
citation: "21 C.F.R. § 520.1638"
title: "21"
number: "520.1638"
heading: "Oxibendazole."
url: "https://uscodex.org/cfr/21/520.1638"
---

# §520.1638. Oxibendazole.

- (a) **Specifications.**
  - (1) Each gram of paste contains 227 milligrams (mg) (22.7 percent) oxibendazole.
  - (2) **Each milliliter of suspension contains 100 mg (10 percent) oxibendazole.**
- (b) **Sponsor.** See No. 054771 in [§ 510.600(c)](/cfr/21/510.600.md?p=c) of this chapter.
- (c) **Special considerations.**
  - (1) See [§ 500.25](/cfr/21/500.25.md) of this chapter.
  - (2) Suspension product described in [paragraph (a)(2)](#a-2) of this section shall be labeled: “Federal law restricts this drug to use by or on the order of a licensed veterinarian.”
- (d) **Conditions of use in horses—**
  - (1) **Amount.** For uses other than for threadworms (Strongyloides westeri), 10 mg oxibendazole per kilogram (/kg) body weight; for threadworms (Strongyloides westeri), 15 mg/kg. Horses maintained on premises where reinfection is likely to occur should be re-treated in 6 to 8 weeks. Administer suspension product by stomach tube in 3 to 4 pints of warm water, or by top dressing or mixing into a portion of the normal grain ration.
  - (2) **Indications for use.** For removal and control of large strongyles (Strongylus edentatus, S. equinus, S. vulgaris); small strongyles (genera Cylicostephanus, Cylicocyclus, Cyathostomum, Triodontophorus, Cylicodontophorus, and Gyalocephalus); large roundworms (Parascaris equorum); pinworms (Oxyuris equi) including various larval stages; and threadworms (Strongyloides westeri).
  - (3) **Limitations.** Do not use in horses intended for human consumption.

## Notes

### Amendments

[78 FR 28825, May 20, 2014]

### Authority

Authority: 21 U.S.C. 360b.

### Source

Source: 40 FR 13838, Mar. 27, 1975, unless otherwise noted.

### Amendments

[78 FR 28825, May 20, 2014]