From Wikipedia, the free encyclopedia
Povidone-iodine (PVP-I) is a stable chemical complex of polyvinylpyrrolidone (povidone, PVP) and elemental iodine. It contains from 9.0% to 12.0% available iodine, calculated on a dry basis[1].
This unique complex was discovered at the Industrial Toxicology Laboratories in Philadelphia by H. A. Shelanski and M. V. Shelanski[2]. They carried out in vitro tests to demonstrate antibacterial activity, and found that the complex was less toxic than tincture of iodine in mice. Human clinical trials showed the product to be superior to other iodine formulations.[3]
It was first sold in 1955, and has since become the universally preferred iodine disinfectant. [4]
[edit] Properties
PVP-I is completely soluble in cold water, ethyl alcohol, isopropyl alcohol, polyethylene glycol, and glycerol. Its stability in solution is much greater than that of tincture of iodine or Lugol's solution.
Free iodine, slowly liberated from the povoiodine-iodine (PVPI) complex in solution, kills eukaryotic or prokaryotic cells through iodination of lipids and oxidation of cytoplasmic and membrane compounds. This agent exhibits a broad range of microbicidal activity against bacteria, fungi, protozoa, and viruses. Slow release of iodine from the PVPI complex in solution minimizes iodine toxicity towards mammalian cells.
Following the discovery of iodine by Bernard Courtois in 1811, it has been broadly used for the prevention and treatment of skin infections, and the treatment of wounds. Iodine has been recognized as an effective broad-spectrum bactericide, and it is also effective against yeasts, molds, fungi, viruses, and proteases. Drawbacks to its use in the form of aqueous solutions include irritation at the site of application, toxicity and the staining of surrounding tissues. These deficiencies were overcome by the discovery and use of povidone-iodine, in which the iodine is carried in a complexed form and the concentration of free iodine is very low. The product thus serves as an iodophor. In addition, it has been demonstrated that bacteria do not develop resistance to PVP-I[5], and the sensitization rate to the product is only 0.7%[6] 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. It is available without a prescription under the generic name povidone-iodine or the brand name Betadine.
[edit] Notes and references
- ^ United States Pharmacopeia
- ^ U.S.patent 2,739,922
- ^ Walter Sneader in Drug Discovery: A History, p 68. New York: John Wiley & Sons, 2005
- ^ Walter Sneader in Drug Discovery: A History, p 68. New York: John Wiley & Sons, 2005
- ^ W.Fleischer and K.Reimer: Povidone-iodine in antisepsis — State of the art, Dermatology, 195(Suppl 2) 3–9 (1997)
- ^ R.Niedner: Cytotoxicity and sensitization of povidone-iodine and other frequently used anti-infective agents, Dermatology, 195(Suppl 2) 89–92 (1997)
[edit] See also
