As noted in Table 2, the FDA TFM of 1994 classified povidone iodine, 5 to 10%, as a Category I agent, i.e., generally safe and effective for use in antiseptic hand wash or HCW handwash products.26 Povidone iodine is an iodophor composed of elemental iodine, iodide or triiodide, and a polymer carrier or complexing agent. The amount of free iodine determines the level of antimicrobial activity of iodophors.32 Iodine molecules rapidly penetrate the microbial cell wall and inactivate cells by forming complexes with amino acids and unsaturated fatty acids, resulting in impaired protein synthesis and alteration of cell membranes. The extent to which iodophors exhibit persistent antimicrobial activity is unclear.1
Antiseptic hand wash (Box 3) with povidone iodine removes or destroys transient microorganisms and reduces the resident hand flora. It is an acceptable method of hand antisepsis (Table 3) in clinical situations when the hands are not visibly soiled; however, the CDC and the WHO recommend the use of an alcohol-based hand rub (Box 2) for routine hand hygiene.1,24,26 In addition, antiseptic handwash with povidone iodine is an acceptable alternative to handwashing (Box 1).
The antimicrobial activity of iodophors can be affected by both organic (e.g., blood and sputum) and inorganic compounds (e.g., alcohols and detergents).33 Iodophors cause less skin irritation (irritant contact dermatitis) and fewer allergic contact dermatitis than iodine, but more irritant contact dermatitis than other antiseptic agents.35 Occasionally, povidone iodine antiseptic agents have become contaminated with gram-negative bacilli and have caused outbreaks of nosocomial infection.32