---
kind: "section"
citation: "21 C.F.R. § 520.1120b"
title: "21"
number: "520.1120b"
heading: "Haloxon boluses."
url: "https://uscodex.org/cfr/21/520.1120b"
---

# §520.1120b. Haloxon boluses.

- (a) **Specifications.** Each bolus contains 10.1 grams of haloxon.
- (b) **Sponsor.** See No. 000061 in [§ 510.600(c)](/cfr/21/510.600.md?p=c) of this chapter.
- (c) **Related tolerances.** See [§ 556.310](/cfr/21/556.310.md) of this chapter.
- (d) **Conditions of use in cattle—**
  - (1) **Amount.** Administered one bolus per 500 pounds body weight (35 to 50 milligrams per kilogram of body weight). Retreat in 3 to 4 weeks.
  - (2) **Indications for use.** For control of gastrointestinal roundworms of the genera Haemonchus, Ostertagia, Trichostrongylus, and Cooperia.
  - (3) **Limitations.** Do not treat dairy animals of breeding age or older. Do not treat within 1 week of slaughter.

## Notes

### Amendments

[40 FR 13838, Mar. 27, 1975, as amended at 44 FR 61591, Oct. 29, 1979; 46 FR 48642, Oct. 2, 1981; 61 FR 8873, Mar. 6, 1996; 62 FR 61625, Nov. 19, 1997; 78 FR 28822, May 20, 2014]

### Authority

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

### Source

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

### Amendments

[40 FR 13838, Mar. 27, 1975, as amended at 44 FR 61591, Oct. 29, 1979; 46 FR 48642, Oct. 2, 1981; 61 FR 8873, Mar. 6, 1996; 62 FR 61625, Nov. 19, 1997; 78 FR 28822, May 20, 2014]