Abstract
Benzalkonium salts comprise a group of positively charged surface-active alkylamine biocides with the general formula alkyldi-methylbenzylammonium chloride or bromide. They interact with guanine nucleotide triphosphate-binding proteins (G proteins), thereby affecting signal transduction in a variety of cell types and processes. The present report reviews the known and potential basic science research and clinical applications and manifestations of benzalkonium salts. Benzalkonium salts have antiproliferative effects on a variety of cells (including T cells) through G-protein-dependent pathways, affect cytokine gene expression (downregulate tumor necrosis factor expression), and are also effective bactericidal, fungicidal, and virucidal agents with multisite (direct and immunologically-mediated) inhibitory activity against many pathogens, including the human immunodeficiency virus (HIV), papillomavirus, and herpesviruses. Therefore, benzalkonium salts not only appear to be effective as disinfectants and spermicides but may also prove useful in the prevention and treatment of several diseases, particularly those linked to viruses and originating at the skin or mucosal surface. The untoward effects of benzalkonium salts are also discussed as a paradigm for chemical-induced diseases.