Dettol Antiseptic Ingredients. Disinfectants and cleaning supplies next to a sink. Overview. Dettol, an antiseptic cleaning product made by Reckitt Benckiser, was developed based on modifications of phenol, an antiseptic that kills germs, discovered in 1860, by Joseph Lister. The active ingredient in dettol is cholroxylenol B.P.4.8%w/v. The other ingredients include isopropyl alcohol, pine oil, castor oil soap, caramel and water.