Excipient (pharmacologically inactive substance)
What is it?
Erythrosine (C20H8I4O5) is commonly referred to as red dye #3. FDA has regulatory oversight for color additives used in foods, drugs, cosmetics, and medical devices. Red Dye #3 can be used in food and drugs per the FDA. According to the FDA, FD&C Red No. 3 may be safely used for coloring foods generally (including dietary supplements) in amounts consistent with good manufacturing practice. Red Dye #3 is commonly used to color maraschino cherries. FD&C Red No. 3 is a synthetic dye with a cherry-pink stain. In foods it is used to dye cake decorating gel, candies and popsicles, among other food items. It is an azo dye, and due to this fact has been replaced with Red #40 (Allura Red), but can still be found in use in the food industry. It is also used as color additive for ingested drugs. It is not listed as approved for use in cosmetics.
 FDA. Electronic Code of Federal Regulations. Part 74—Listing of color additives subject to certification. http://www.ecfr.gov/cgi-bin/text-idx?SID=2530cfa24a67950ea5ed73ca84d9d594&node=21:126.96.36.199.28&rgn=div5
 Electronic Code of Federal Registers. Title 21: Food and Drugs. Part 74. Listing of color additives subject to certification. Subpart B. Drugs. Accessed online October 19, 2011. http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr;sid=c387334e82029536a53dde1171ba5481;rgn=div5;view=text;node=21%3A188.8.131.52.27;idno=21;cc=ecfr#21:184.108.40.206.220.127.116.11
 U.S. Food and Drug Administration. Color Additives: FDA's Regulatory Process and Historical Perspectives. Accessed 10/20/2011. http://www.fda.gov/ForIndustry/ColorAdditives/RegulatoryProcessHistoricalPerspectives/default.htm