659-40-5

Preservative in cosmetics.

Hexamidine diisethionate (HEX D) is an organic salt form of Hexamidine, which has been used as an antimicrobial agent in the personal care industry and in a variety of over-the-counter (OTC) products. For example, 0.05% HEX D solution (Keratosept?) is a new antimicrobial drop for the treatment of eye infections and is better tolerated than povidone iodine. In personal care, Hexamidine has adverse reactions such as photosensitivity and contact allergy. Therefore, the European safety assessment recommends that the content of HEX D in leave-on and rinse-off cosmetics should not exceed 0.1%^[1-2].

White or slightly yellow powder, hygroscopic

Notclassified

Acute oral LD(50) values of Hexamidine Diisethionate were 0.71 to 2.5 g/kg in mice and 0.75 g/kg in rats. Dermal exposure to 4 g/kg Hexamidine Diisethionate in rats or up to 9.4 ml/kg of a 0.1% Hexamidine Diisethionate solution under occlusion in rabbits produced no mortality or other signs of toxicity. The no-observed-effect level (NOEL) for oral subchronic toxicity of Hexamidine Diisethionate in rats was 50 mg/kg/day. No signs of toxicity were observed with 2% Hexamidine Diisethionate in subchronic studies using rabbits. Application of 0.1 ml of 0.11% Hexamidine Diisethionate in aqueous solution to the eyes of rabbits produced transient reactions; 0.05% produced no reactions. Slight erythema was observed with 0.10% Hexamidine Diisethionate applied to the abraded skin of 1/11 albino rabbits. A 40% solution of Hexamidine Diisethionate applied to 10% of the body surface of rats produced slight erythema, slight edema, and scabbing in some animals at varying times after treatment. Hexamidine Diisethionate was not a sensitizer in the guinea pig maximization test or in an intracutaneous guinea pig sensitization test. Hexamidine Diisethionate was not a photosensitizer in albino rabbits. Hexamidine Diisethionate was not mutagenic in a bacterial reverse mutagenicity assay or clastogenic in mammalian cells. Hexamidine Diisethionate at 0.10% did not provoke primary irritation, inflammation, or sensitization in a clinical test of 200 human subjects^[1].

[1] Final report on the safety assessment of Hexamidine and Hexamidine Diisethionate.[J]. International Journal of Toxicology, 2007, 26 Suppl 3: 79-88. DOI:10.1080/10915810701663168.
[2] F AVOGARO. Intravitreal injections primary prevention: a case-control study.[J]. European review for medical and pharmacological sciences, 2023, 27 8: 3664-3669. DOI:10.26355/eurrev\_202304\_32153.