The mythology of povidone-iodine and the development of self-sterilizing plastics.

The predominance of elemental iodine as a chemical antiseptic has been established during a century. Free iodine is effective for treatment and prevention of infection. Iodophors, such as povidone-iodine, have replaced elemental iodine in clinical use. Toxic absorption of povidone-iodine occurs from all tissues except intact adult skin, to which its use should be restricted. Povidone-iodine binds iodine so firmly that insufficient free iodine is released to be effective for treating or preventing infection. It is a weak antiseptic that is marginally acceptable as a disinfectant for adult skin. The shortcomings of povidone-iodine stimulated a search for iodophors that would liberate therapeutically effective concentrations of free iodine. These investigations led to a new self-sterilizing plastic formed by the complexing of polyurethane and iodine.