Patch testing to exclude allergic contact dermatitis caused by povidone-iodine.

Povidone-iodine (polyvinylpyrrolidone-iodine, PVP-I) solution is an effective and safe disinfectant agent used throughout the world; however, prolonged exposure to PVP-I solution may cause irritation or rarely severe skin reactions. When PVP-I as is in the aqueous state is used for patch testing, a false-positive result is likely to arise due to irritation. Patch testing to exclude allergic contact dermatitis caused by PVP-I should be done with dried 10% PVP-I solution, 10% PVP-I gel, 8% sodium thiosulfuric acid and a mixture of 10% PVP-I solution and 8% sodium thiosulfuric acid. Copyright 2002 S. Karger AG, Basel