Merbromin

Uses

Merbromin's best-known use is as a topical antiseptic to treat minor wounds, burns, and scratches. Merbromin is also antimicrobial. It is also used in the antisepsis of the umbilical cord, and the antisepsis of wounds with inhibited scar formation, such as neuropathic ulcers and diabetic foot sores. When applied on a wound, it stains the skin a distinctive carmine red, which can persist through repeated washings. Due to its persistence and to its lethality to bacteria, Merbromin is useful on infections of the fingernail or toenail.

In 1998, the U.S. Food and Drug Administration reclassified merbromin from "generally recognized as safe" to "untested," due to a lack of recent studies or updated supporting information. Consequently, its use in the United States has been superseded by other agents (e.g., povidone iodine, benzalkonium chloride, chloroxylenol).

Synthesis

Merbromin is synthesized by combining dibromofluorescein with mercuric acetate and sodium hydroxide or, alternatively, through action of the mercuric acetate upon (or combining with) sodium dibromofluorescein.  Because of its anionic character, it is chemically incompatible with acids, the majority of alkaloid salts and most local anesthetics.

Mercurochrome

Merbromin is sold under the trade name Mercurochrome (in which the suffix "-chrome" denotes "color"). The name is also commonly used for over-the-counter antiseptic solutions consisting of merbromin (typically at 2% concentration) dissolved in either ethyl alcohol (tincture) or water (aqueous).

Its antiseptic qualities were discovered in 1918 by Hugh H. Young, a physician at Johns Hopkins Hospital. The chemical soon became popular among parents and physicians for everyday antiseptic uses, in part because the dye component made it easy to see where the antiseptic had been applied.

On 19 October 1998, citing potential for mercury poisoning, the US Food and Drug Administration (FDA) reclassified merbromin from "generally recognized as safe" to "untested," effectively halting its distribution within the United States. Sales were subsequently halted in Brazil (2001), Germany (2003), and France (2006). It remains readily available in most other countries.

Within the United States, products such as Humco Mercuroclear ("Aqueous solution of benzalkonium chloride and lidocaine hydrochloride") play on the brand recognition history of Mercurochrome but substitute other ingredients with similar properties. In Canada, Jean Coutu Group markets a chlorhexidine solution under the name Mercurochrome.

References

References

1. (January 2018). "Prospecto autorizado Mercromina Film ®".
2. Sellares Casas, E. "Eficacia de una aplicación frente a 3 de merbromina en el tiempo de caída del cordón". Acta Pediátrica Española.
3. Gaitan Enríquez, J. (September 1997). "Merbromina como tratamiento de elección en úlceras de pie diabético". Clínica Rural.
4. (22 April 1998). "Status of Certain Additional Over-the-Counter Drug Category II and III Active Ingredients". Federal Register.
5. (1989). "The Merck Index, An Encyclopedia of Chemicals, Drugs, and Biologicals". Merck & Co.
6. "Mercurochrome". Centre National de Ressources Textuelles et Lexicales.
7. Young, Hugh. (November 15, 1919). "A New Germicide for Use in the Genito-Urinary Tract: Mercurochrome-220". Journal of the American Medical Association.
8. (30 April 2009). "Quantitative and Qualitative Analysis of Mercury Compounds in the List". [[U.S. Food and Drug Administration]].
9. (22 September 2003). "Merbromin im Spiegel der Expertenmeinungen".
10. "Mercuroclear MSDS". Humco.
11. "Antiseptique solution de premiers soins sans mercure, 25 ml – Personnelle : Désinfectant".