Name: Povidone iodine
Synonyms: Povidone iodine USP; Betadine; Isodine; Ultradine; 1-Vinyl-2-pyrrolidinone polymers iodine complex; PVP-I
Molecular Formula: C6H9I2NO
Molecular Weight: 364.95
CAS Registry Number: 25655-41-8
Melting point: 300 ºC
Povidone-iodine is a broad spectrum antiseptic for topical application in the treatment and prevention of wound infection. It may be used in first aid for minor cuts, burns, abrasions and blisters. Povidone-iodine exhibits longer lasting antiseptic effects than tincture of iodine, due to its slow absorption via soft tissue, making it the choice for longer surgeries. Chlorhexidine provides superior results with equivalent adverse events.
Consequently, PVP-I has found broad application in medicine as a surgical scrub; for pre- and post-operative skin cleansing; for the treatment and prevention of infections in wounds, ulcers, cuts and burns; for the treatment of infections in decubitus ulcers and stasis ulcers; in gynecology for vaginitis associated with candidal, trichomonal or mixed infections. For these purposes PVP-I has been formulated at concentrations of 7.5–10.0% in solution, spray, surgical scrub, ointment, and swab dosage forms; however, use of 10% povidone-iodine though recommended, is infrequently used, as it is poorly accepted by health care workers and is excessively slow to dry.
Because of these critical indications, only sterile povidone-iodine should be used in most cases. Non-sterile product can be appropriate in limited circumstances in which people have intact, healthy skin that will not be compromised or cut. The non-sterile form of Povidone iodine has a long history of intrinsic contamination with Burkholderia cepacia (aka Pseudomonas cepacia), and other opportunistic pathogens. Its ability to harbor such microbes further underscores the importance of using sterile products in any clinical setting. Since these bacteria are resistant to povidone iodine, statements that bacteria do not develop resistance to PVP-I, should be regarded with great caution: some bacteria are intrinsically resistant to a range of biocides including povidone-iodine.
Antiseptic activity of PVP-I is because of free iodine (I2) and PVP-I only acts as carrier of I2 to the target cells. Most commonly used 10% PVP-I delivers about 1-3 ppm of I2 in a compound of more than 31,600 ppm of total iodine atoms. All the toxic and staining effects of PVP-I is due to the inactive iodine only.