---
kind: "section"
citation: "21 C.F.R. § 573.496"
title: "21"
number: "573.496"
heading: "Guanidinoacetic acid."
url: "https://uscodex.org/cfr/21/573.496"
---

# §573.496. Guanidinoacetic acid.


The food additive, guanidinoacetic acid, may be safely used in poultry feeds in accordance with the following prescribed conditions:

- (a) **The additive is manufactured by reacting glycine with cyanamide in an aqueous solution.**
- (b) The additive is used or intended for use at levels not to exceed 0.12 percent of the complete feed:
  - (1) To spare arginine in broiler chicken and turkey feeds; or
  - (2) **As a precursor of creatine in poultry feeds.**
- (c) The additive consists of not less than 97 percent guanidinoacetic acid [N-(aminoiminomethyl)-glycine] (CAS 352-97-6) by weight.
- (d) **The additive meets the following specifications—**
  - (1) Dicyandiamide not to exceed 0.5 percent;
  - (2) Cyanamide not to exceed 0.01 percent;
  - (3) Melamine not to exceed 15 parts per million (ppm);
  - (4) Sum of ammeline, ammelide, and cyanuric acid not to exceed 35 ppm; and
  - (5) **Water not to exceed 1 percent.**
- (e) To assure safe use of the additive in addition to the other information required by the Federal Food, Drug, and Cosmetic Act:
  - (1) The label and labeling of the additive, any feed premix, and complete feed shall contain the name of the additive.
  - (2) The label and labeling of the additive and any feed premix shall also contain:
    - (i) A statement to indicate the maximum use level of guanidinoacetic acid must not exceed 0.12 percent of the complete feed for poultry; and
    - (ii) **Adequate directions for use.**

## Notes

### Amendments

[81 FR 86269, Nov. 30, 2016, as amended at 86 FR 37038, July 14, 2021]

### Authority

Authority: 21 U.S.C. 321, 342, 348.

### Source

Source: 41 FR 38652, Sept. 10, 1976, unless otherwise noted.

### Amendments

[81 FR 86269, Nov. 30, 2016, as amended at 86 FR 37038, July 14, 2021]