Iodine made easy

這篇文章 Iodine made easy 發表於 2011年五月. 
Why is iodine safer today? Iodophors were developed in the 1950s to overcome the side effects associated with elemental iodine. These were found to be safer and less painful, but just as effective as elemental iodine, allowing widespread use. Bonding iodine with another molecule makes it less toxic and instead of high concentrations of iodine being released in a single application, the iodine is slowly released from the reservoir carrier molecule over a sustained period of time. Iodophors are preparations that bind iodine to a solubilising agent or carrier. The water-soluble complex allows the slow release of a low concentration of free iodine when the carrier comes into contact with wound exudate. This controlled release of low concentrations of iodine helps to minimise the negative side effects of using free elemental iodine. 

When is iodine indicated? An international consensus document on managing wound infection27, recommends the use of antiseptic dressings as being part of an overall management plan in the following circumstances: n to prevent wound infection or recurrence of infection in patients at greatly increased risk of infection n to treat localised infection n to treat spreading infection when healing is delayed Slow release iodine dressings have been used to treat a range of wound types where infection is present or suspected. These include pressure ulcers, venous leg ulcers, diabetic foot ulcers, minor burns and superficial skin-loss injuries24,28.

When are iodine dressings contraindicated? Iodine dressings must be used under medical supervision in patients with thyroid diseases, known or suspected iodine sensitivity, in pregnant or breastfeeding women or in newborn babies and up to the age of six months8 . Long-term use of PVP-I has been loosely associated with mild hyperthyroidism29 and long-term use is not recommended for patients with impaired thyroid function. However, a number of studies have monitored thyroid function during PVP-I clinical trials and have reported that it remains unchanged30–32. To avoid toxicity or the hypothetical risk of thyroid-related complications, iodine products should be used with caution in children, in those with large burn areas, and where prolonged treatment of large open wounds is required. The use of iodine dressings should also be avoided

before and after the use of radio-iodine diagnostic tests (until permanent healing). Reports of systemic effects following short-term PVP-I treatment are extremely rare. Iodine absorption has been found to be dependent on the size of the wound and the duration of treatment33. Hunt et al31 also discovered a relationship between wound area and iodine levels in serum and urine following the treatment of burn wounds with PVP-I, but it was proposed that renal function was a factor in the determination of this. Iodine should, therefore be avoided in patients with significant renal disease.


Summary Although it has been speculated that iodine delays healing and is cytotoxic, there is substantial evidence to suggest that the commonly-used low concentration, slow release iodophors improve healing rates and are effective as highly potent antimicrobials with a broad spectrum of activity, including antibiotic-resistant strains such as MRSA. It is unfortunate that the concerns about iodine are based on studies that are so varied in method and design that it is difficult to draw reliable comparisons and conclusions. The reputation of iodine wound products, used as antimicrobials, suffered as a result of these studies but it is now widely accepted that slow-releasing iodophor antimicrobials are safe and have minimal detrimental impact on wound healing