21 CFR § 74.1304 - Fd&c Red No. 4.
---
identifier: "/us/cfr/t21/s74.1304"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 74.1304 - FD&C Red No. 4."
title_number: 21
title_name: "Food and Drugs"
section_number: "74.1304"
section_name: "FD&C Red No. 4."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "A"
subchapter_name: "GENERAL"
part_number: "74"
part_name: "LISTING OF COLOR ADDITIVES SUBJECT TO CERTIFICATION"
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. 321, 341, 342, 343, 348, 351, 352, 355, 361, 362, 371, 379e."
regulatory_source: "42 FR 15654, Mar. 22, 1977, unless otherwise noted."
cfr_part: "74"
---
# 74.1304 FD&C Red No. 4.
(a) *Identity.* (1) The color additive FD&C Red No. 4 is principally the disodium salt of 3-[(2,4-dimethyl-5-sulfophenyl)azo] -4-hydroxy-1-naphthalenesulfonic acid.
(2) Color additive mixtures for use in externally applied drugs made with FD&C Red No. 4 may contain only those diluents that are suitable and that are listed in part 73 of this chapter for use in color additive mixtures for coloring externally applied drugs.
(b) *Specifications.* FD&C Red No. 4 shall conform to the following specifications and shall be free from impurities other than those named to the extent that such impurities may be avoided by good manufacturing practice:
Sum of volatile matter (at 135 °C.) and chlorides and sulfates (calculated as sodium salts), not more than 13 percent.
Water-insoluble matter, not more than 0.2 percent.
5-Amino-2,4-dimethyl-1-benzenesulfonic acid, sodium salt, not more than 0.2 percent.
4-Hydroxy-1-naphthalenesulfonic acid, sodium salt, not more than 0.2 percent.
Subsidiary colors, not more than 2 percent.
Lead (as Pb), not more than 10 parts per million.
Arsenic (as As), not more than 3 parts per million.
Mercury (as Hg), not more than 1 part per million.
Total color, not less than 87 percent.
(c) *Uses and restrictions.* FD&C Red No. 4 may be safely used in externally applied drugs in amounts consistent with good manufacturing practice.
(d) *Labeling.* The label of the color additive and any mixtures prepared therefrom intended solely or in part for coloring purposes shall conform to the requirements of § 70.25 of this chapter.
(e) *Certification.* All batches of FD&C Red No. 4 shall be certified in accordance with regulations in part 80 of this chapter.