Iodine has been used in wound care for more than 170 years. There have been reviews of its antimicrobial activity, chemical properties, clinical effectiveness and cytotoxicity (Cooper, 2007; Vermeulen et al, 2010). Iodine products reduce bacterial load and are active against bacteria, mycobacterium, fungi, protozoa and viruses, and can be used to treat both acute and chronic wounds (Cooper, 2004), particularly chronic wounds (Leaper and Durani, 2008).
Iodine is used both to clean and prepare the wound bed and to manage wound infection (Leaper and Durani, 2008). Topical application is known to provide effective antibacterial prophylaxis in wound care, particularly burns (Lawrence, 1998). It is important to note that in vitro and in vivo studies have commented on the cytotoxic effects of iodine (Close-Tweedie, 2001). In an animal study, cadexomer iodine dressings significantly reduced meticillin-resistant Staphylococcus aureus (MRSA) and the total bacteria in the wounds when compared to controls (Mertz et al, 1999). Iodine-based antiseptics are relatively cheap; however, concerns about allergic reactions and systemic toxicity still need further investigation.
Iodine is available in different formulations, including spray, cream solution, and wound dressings.
In modern wound management iodine is used in two forms:
- Povidone iodine
- Cadexomer iodine.
How does iodine work?
The attributes of iodine are:
- Antimicrobial activity (Sibbald et al, 2011)
- De-sloughing capability — cadexomer preparations
- Cadexomer iodine may increase epithelialisation of chronic wounds (Metz, et al, 1984; Lamme et al, 1998).
Not all iodine products are the same and the manufacturers’ instructions should be considered when treating different wound types.
There are two main types of iodine products available, how do I select the right one?
Each patient has different needs that need to be considered when choosing the correct product. The following questions can help with dressing selection.
How much exudate is the wound producing?
If the wound is producing medium to high volumes of exudate, a plus or superabsorbent product may be required. However, if exudate production is low, a light or thin dressing may be more suitable. Correct exudate assessment (based on colour and amount) and management is essential both to maintain a moist wound healing environment and to prevent the peri-wound skin from maceration.
Methods for assessing exudate have been suggested by Falanga (2000), Bates-Jensen wound assessment tool (Bates-Jensen, 2007; and a proposed national wound assessment form (Fletcher, 2010). The latter uses the term ‘wound moisture level’ rather than exudate, and is based on the World Union of Wound Healing Societies (WUWHS) document on exudate (WUWHS, 2007). Clinicians should also refer to their local policy on exudate assessment.
How fragile is the patient’s skin: adherent or non-adherent?
Non-adherent iodine does not stick to the skin and a secondary dressing may be required. These dressings are suitable for use on fragile or damaged skin, where adhesive dressings may result in skin damage.
Is the dressing going to be used under compression?
While some iodine dressings can be used under compression, others hold fluid under pressure. This means that if pressure is applied, such as by compression bandaging, or by body weight if the dressing is placed on the sacrum or heel, the fluid in the dressing may leak out. In such circumstances, dressings which have the ability to wick and lock fluid away should be used.
Is antimicrobial action needed?
Iodine dressings have antimicrobial components, which help the dressings to kill microorganisms that may be responsible for local wound infection or delayed healing. Antimicrobial dressings should only be used if infection is present, or if the patient is considered to be at an increased risk of wound infection.
Does the wound need protection?
Povidone-iodine can be used in the prevention and management of infection in minor burns, skin injuries and ulcers. Cadexomer iodine can be used to treat chronic exudating wounds. Manufacturers’ instructions should always be followed.
Where is the wound? Is it in a place that is difficult to dress?
Some wound sites such as the sacrum or heel can be difficult to dress. Iodine solutions and dressings can be used to treat most anatomical areas.
Selecting an iodine product
Selection of an iodine product should be guided by:
- Volume of exudate
- Condition of skin
- Location of wound
- Use under compression
- Presence of infection.
Although cost-effectiveness is important, choosing iodine solutions and dressings is not necessarily the best thing to do, as dressing choice should always be guided by the patient’s needs. If a dressing fails to perform well, more frequent dressing changes will be needed incurring greater nursing time.
Patient choice and preference should always be considered. This helps to build up a good nurse–patient relationship, and is in line with national policy.
Wound care specialists should ensure that iodine is not used where there is known iodine hypersensitivity, pregnancy, renal impairment, or on children, mothers who are breastfeeding or patients with thyroid disease. The use of iodine should always be under medical supervision. Furthermore, as there are a variety of iodine solutions and dressings available on the market, contraindications and cautions must always be considered.
- Secondary dressing required
- Can be used under compression
Bates-Jensen B (1997) The pressure sore status tool a few thousand assessments later. Adv Wound Care 10(5): 65–73
Close-Tweedie J (2001) The role of povidone iodine in podiatric chronic wound care. J Wound Care 10(8): 339–42
Cooper RA (2004) A review of the evidence for the use of topical antimicrobial agents in wound care. World Wide Wounds 2004 Available online.
Cooper RA (2007) Iodine revisited. Int Wound J 4(2): 124–37
Falanga V (2000) Classifications for wound bed preparation and stimulation of chronic wounds. Wound Rep Regen 8(5): 347–52
Fletcher J (2010) Development of a new wound assessment form. Wounds UK 6(1): 92–9
Lamme EN, Gustafsson TO, Middelkoop E (1998) Cadexomer iodine shows stimulation of epidermal regeneration in experimental full thickness wounds. Arch Dermatol Res 290: 18–24
Leaper DJ, Durani P (2008) Topical antimicrobial therapy of chronic wounds healing by secondary intention using iodine products. Int Wound J 5(2): 361–8
Mertz PM, Alvarez OM, Smerbeck RV, Eaglstein WH (1984) A new in vivo model for the evaluation of topical antiseptics on superficial wounds. Arch Dermatol 120: 58–62
Mertz PM, Oliveira-Gandia MF, Davis SC (1999) The evaluation of a cadexomer iodine wound dressing on methicillin-resistant Staphylococcus aureus in acute wounds. Dermatol Surg 25: 89–93
Sibbald RG, Leaper DJ, Queen D (2011) Iodine Made Easy. Wounds Int 2(2): 1–4
Vermeulen H, Westerbos SJ, Ubbink DT (2010) Benefit and harm of iodine in wound care: a systematic review. Hosp Infect 76: 191–9
World Union of Wound Healing Societies (2007) Principles of Best Practice: Wound Exudate and the Role of Dressings. A Consensus Document. Available online.