Iodine has long been in use as an antibacterial agent and a skin disinfectant. It was discovered in 1811, and gained widespread popularity during the American Civil War, where it was used liberally to treat the wounds of soldiers. In its original form, iodine caused pain and irritation when applied to wounds, it has been shown to impair the function of cells involved in wound healing, and it also had the unfortunate side effect of skin discoloration.
Since the late 1940’s, newer, safer, and less painful formulations of iodine in the form of iodophors have come into use. These products release sustained low levels of iodine, which bind to proteins, fatty acids, and nucleotides. These products have a broad spectrum of activity against bacteria, mycobacterium, fungi, and protozoa.
Cadexomer iodine is a slow release antimicrobial which has the capability to absorb excess wound exudate while maintaining a sustained level of iodine in the wound bed. Cadexomer iodine is available both as a dressing and as an ointment. In studies it has been shown to be effective in reducing counts of MRSA (methicillin-resistant staphylococcus aureus) and Pseudomonas aeruginosa. It is estimated that 1 gram of Cadexomer iodine can absorb as much as 7 ml of fluid. The iodine is slowly released as the iodine is absorbed, which helps to reduce the bacterial load while simultaneously debriding the wound. It requires moisture to be activated. Unlike povidone iodine dressings which release iodine immediately upon application, the sustained release of iodine from cadexomer iodine dressings does not cause cytotoxic effects.
Studies have shown that cadexomer iodine is effective in healing chronic ulcers; however, one of the serious potential side effects of using iodine for the treatment of wounds is that there is the potential for the absorption of iodine. For this reason, thyroid function should be monitored in patients who use this therapy for extended periods of time. In addition, iodine can interact negatively with lithium, and should be used with caution in patients who are on lithium concurrently. Iodine should not be used at the same time as mercurial antiseptics, such as mercurochrome.
Given the growing concern over the rise of antibiotic-resistant organisms, cadexomer iodine is an effective alternative for the treatment of chronic wounds. Reports of resistance to iodine are scarce, despite the fact that iodine has been in use for over 150 years. Cadexomer iodine can be safely used on most patients (providing they are not sensitive to iodine itself) and provides good coverage of bacteria, mycobacterium, fungi, and protozoa, as well as being effective against MRSA.