Dequalinium is a quaternary ammonium cation commonly available as the dichloride salt. The bromide, iodide, acetate, and undecenoate salts are known as well. Dequalinium chloride is the active ingredient of several medications:
Dequalinium salts may be used to treat malaria. As dequalinium chloride, it can be used in lozenges to cure sore throats however while this is effective in vitro, it is not effective in cases of streptococci infections 
Gamboa-Vujicic, Gisela; Emma, Dennis A.; Liao, Shu Y.; Fuchtner, Carlos; Manetta, Alberto (1993). "Toxicity of the mitochondrial poison dequalinium chloride in a murine model system". Journal of Pharmaceutical Sciences82 (3): 231–5. doi:10.1002/jps.2600820302. PMID8450414.