---
kind: "section"
citation: "21 C.F.R. § 558.630"
title: "21"
number: "558.630"
heading: "Tylosin and sulfamethazine."
url: "https://uscodex.org/cfr/21/558.630"
---

# §558.630. Tylosin and sulfamethazine.

- (a) **Specifications.** Type A medicated articles containing equal amounts of tylosin phosphate and sulfamethazine, available in concentrations of 5, 10, 20, or 40 grams each, per pound.
- (b) **Sponsors.** See sponsor numbers in [§ 510.600(c)](/cfr/21/510.600.md?p=c) of this chapter.
  - (1) **No.** 058198 for use as in paragraph (e)(1) of this section.
  - (2) **No.** 066104: 10 or 40 grams per pound each for use as in paragraph (e)(2) of this section.
- (c) **Related tolerances.** See §§ [556.670](/cfr/21/556.670.md) and [556.746](/cfr/21/556.746.md) of this chapter.
- (d) **Special considerations.**
  - (1) Federal law restricts medicated feed containing this veterinary feed directive (VFD) drug to use by or on the order of a licensed veterinarian. See [§ 558.6](/cfr/21/558.6.md) for additional requirements.
  - (2) The expiration date of VFDs for tylosin and sulfamethazine medicated feeds must not exceed 6 months from the date of issuance. VFDs for tylosin and sulfamethazine shall not be refilled.
  - (3) Labeling shall bear the statement: “Do not use in medicated feeds containing in excess of 2% bentonite.”
- (e) **Conditions of use.** It is used in feed for swine as follows:

## Notes

### Amendments

[81 FR 95021, Dec. 27, 2016, as amended at 84 FR 33002, July 11, 2019; 91 FR 5303, Feb. 6, 2026]

### Authority

Authority: 21 U.S.C. 354, 360b, 360ccc, 360ccc-1, 371.

### Source

Source: 40 FR 13959, Mar. 27, 1975, unless otherwise noted.

### Amendments

[81 FR 95021, Dec. 27, 2016, as amended at 84 FR 33002, July 11, 2019; 91 FR 5303, Feb. 6, 2026]