Study examines effect of honey on venous leg ulcers

February 1, 2005

Auckland, New Zealand — Researchers here are studying the effectiveness of manuka honey with compression bandaging in the treatment of leg ulcers, according to Andrew Jull, R.N., M.A.

Honey has been used for centuries in wound care and has a good safety profile, says Mr. Jull, a research fellow with the Clinical Trials Research Unit, School of Population Health, University of Auckland.

"Honey has been employed in wound care since the ancients," he notes. Doctors and pharmacopoeists combined it with other agents or used it as a vehicle for such purposes as removing moles and cleaning ulcers.

HALT is a multicenter, open-label trial that aims to enroll 400 participants and randomize them to treatment with or without honey, according to Mr. Jull, who is also a clinical lecturer in the School of Nursing at the university.

"There have been no trials of honey as an adjuvant to compression for venous leg ulcers," Mr. Jull notes. "However, there are now two in progress - the HALT trial and another trial in Ireland, where the main outcome is ulcer debridement."

He points out that approximately 25 case reports or series of honey as a wound treatment have been reported in the literature since the 1970s, involving a wide range of wounds in a total of 360 patients. Also, 10 randomized, controlled studies have been carried out, most of them comparing honey to various other treatments for moderate burns, he adds.

Healing nectar? Manuka honey is derived from the New Zealand tea tree (Leptospermum scoparium) and processed by the honeybee Apis mellifera. A similar honey is derived from the Australian jelly bush tree, also a Leptospermum species.

Consisting of approximately 35 percent glucose, 40 percent fructose, 5 percent sucrose and 20 percent water, bee honey is rich in amino acids, vitamins, minerals and enzymes, says Mr. Jull.

"Honey's antibacterial action is effected through the osmotic effect of the sugars, and the action of very dilute (1 mmol/L) hydrogen peroxide," he explains. "In addition, honey derived from species of tea tree has a unique constituent that enhances its bactericidal action against a wide range of pathogens."

That constituent is known as the unique manuka factor (UMF), identified by Peter Molan, M.D., from the Honey Research Unit, University of Waikato, New Zealand. The UMF rating provides an indication of the strength of the bactericidal activity: UMF 15, for example, means the honey has a non-peroxide activity the equivalent of 15 percent phenol.

"As a wound healing agent, honey appears to draw fluid from the underlying circulation, providing both a moist environment and topical nutrition that may enhance tissue growth," Mr. Jull says. "Histologically, honey appears to stimulate tissue growth in animal and human controlled trials."

Observed benefits include early reparative changes, a reduction in inflammatory changes and improved epithelialization, he reports. Clinically, honey has also been found to effect debriding of wounds.

Few adverse effects Honey appears to be generally well-tolerated as a topical treatment in wounds, Mr. Jull says, based on published controlled trials involving more than 1,200 patients treated with multifloral honey.

In a New Zealand case series of leg ulcers treated with manuka honey, he reports, three of 10 patients treated reported stinging for up to 15 minutes following application of honey, and one participant consequently withdrew from the study.

"This sensation is probably related to the acidity of honey," he observes. "In such cases, there appear to be no adverse histologic sequelae."