by Matthew Regulski, DPM, CWS, FAPWCA
Honey has been used as a wound dressing for centuries. Evidence for its medicinal use has been found in ancient writings, including a papyrus dating to the 17th century B.C. In modern times, it was in common use during World War I and II, but it began to wane in popularity with the rise of antibiotics around 1940. Only in the last decade have microbiologists begun to understand its precise medical benefits and the special properties of one particular variety: active Leptospermum (manuka) honey (Leptospermum scoparium) derived from the pollen and nectar of specific tea tree plants.
Researchers have found the Leptospermum species, which is native to New Zealand, has unique plant-derived components that make it ideal for the management of hard-to-heal wounds and burns, and large-scale, randomized control studies have proven its efficacy.
Active Leptospermum honey can help manage lightly to heavily exuding wounds, such as diabetic foot ulcers, venous stasis leg ulcers, arterial leg ulcers, leg ulcers of mixed etiology, pressure ulcers (I-IV), first- and second-degree burns, donor sites, and traumatic and surgical wounds. The honey cleans a wound and rapidly lifts dead tissue, a process facilitated by the high-sugar content in the honey, which has an osmotic effect. In addition, the honey helps to reduce edema and wound pH, and provides a moist healing environment. What is also notable is all these benefits exist without any toxicity to healthy tissue. The dressings are sterilized by Gamma irradiation. This ensures any contaminants, including clostridium botulinum spores that may be present in unsterilized honey, are eradicated.
Leptospermum honey also has a broad spectrum of bactericidal activities. Recent research revealed medical-grade Leptospermum honey is as effective as a strong combatant against antibiotic-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE). S. aureus is one of the most commonly acquired pathogens in both the community and the hospital settings, and it is particularly problematic in skin and wound infections. The emergence of MRSA and VRE has seriously compromised treatment options. The current issues surrounding antibiotic resistance, and a growing body of evidence supporting the use of honey as a dressing for a wide range of wounds, have increased interest in its clinical use.
Let us examine in greater detail some of the positive therapeutic effects of active Leptospermum honey dressings. Excessive inflammation can prevent healing or cause further tissue damage by increasing reactive oxygen species or free radicals; honey has been shown to reduce both acute and chronic inflammation. Although the mechanism for the anti-inflammatory action of honey is not entirely understood, multiple effects have been reported. For example, histological studies of biopsy specimens show a reduced number of inflammatory cells when exposed to honey. And, honey’s ability to reduce edema not only alleviates associated pain, but also improves microcirculation and increases the availability of dissolved oxygen and nutrients needed for tissue repair and regeneration.
Medical honey may also facilitate wound debridement via several mechanisms. Because of its strong osmotic action, honey pulls lymph fluid from the tissues of a wound to add moisture needed for autolytic debridement. The osmotic action cleanses the wound base removing debris and painlessly lifting off slough and necrotic tissue. Honey may provide a more comfortable and cost-effective method of debridement than mechanical or surgical excision. Additionally, decreased wound odor has been reported when honey dressings were used to treat abscesses, diabetic foot ulcers, leg ulcers and fungating wounds. Honey reduces odor through a pair of mechanisms. First, honey exerts antibacterial action against certain anaerobic bacteria, such as Bacteroides spp., whose presence is believed to cause odor. Second, honey provides glucose as an alternative to the amino acids created when serum and dead cells are metabolized by bacteria. As a result, lactic acid is produced as compared to the malodorous ammonia, amines and sulfur compounds typically formed by the metabolism of amino acids from decomposed serum and tissue proteins when honey is not present.
Lepstospermum honey has been reported to promote wound healing through several mechanisms. It promotes a moist wound environment by drawing lymph into the wound through osmosis and preventing the dressing from adhering to the wound bed. In addition, the levulose and fructose contained in honey may improve local nutrition and promote epithelialization. The acidic nature of honey provides an optimal environment for fibroblast activity. Types of wounds for which honey dressings have been used include skin grafts, infected skin-graft donor sites and infected trauma wounds. Others include necrotizing fasciitis, abscesses, pilonidal sinuses,and pressure ulcers, as well as leg and foot ulcers, leg lacerations, traumatic wounds, tropical ulcers, malignant ulcers, burns and scalds, Hidradenitis suppurativa, meningococcal septicemia skin lesions, surgical wounds, herpetic lesions, atopic dermatitis, animal-bite wounds and rheumatoid ulcers.
Finally, scarless healing has been reported when honey was used in some cavity wounds. Several mechanisms for this phenomenon have been proposed, including the possibility that saccharides at the wound surface may encourage the production of hyaluronic acid from glucose, which simultaneously suppresses the formation of fiber-forming collagens.
As described above, honey—predominately the Leptospermum variety—has been and continues to be a very promising natural ingredient in the quest for improved skin and wound care. Further research will elucidate its properties and has the potential to make it a more attractive option for health care providers and their patients.
Matthew Regulski, DPM, is a partner at Ocean County Foot and Ankle Surgical Associates in Toms River and Forked River, N.J., and director of the Wound Center of Ocean County in Toms River, N.J. He is also affiliated with the Kimball Hospital Wound Care Center in Lakewood, N.J. He can be reached at [email protected].