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:

Dequadin an antiseptic and disinfectant. It is a topical bacteriostat. It is used in wound dressings and mouth infections and may also have antifungal action. It may cause skin ulceration.