Oregano Extract Ointment for Wound Healing: A Randomized, Double-Blind, Petrolatum-Controlled Study Evaluating Efficacy

October 2011 | Volume 10 | Issue 10 | Original Article | 1168 | Copyright © October 2011

Jennifer Ragi MD,a Amy Pappert MD,a Babar Rao MD,a Daphna Havkin-Frenkel PhD,b Sandy Milgraum MDa

aDepartment of Dermatology, University Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Somerset, NJ bDepartment of Plant Pathology and Biology, Rutgers University, New Brunswick, NJ

No significant adverse reactions were noted in either group. Mild pruritus was noted in five patients in the oregano ointment group and six patients in the petrolatum group. One patient in the oregano group and three patients in the petrolatum group noted mild tenderness each of whom had cellulitis.


With the high rate of allergic contact dermatitis to existing topical antibiotics and the increasing prevalence of antibiotic resistance, new classes of antibiotics are needed for wounds. The oregano used in this study was grown from a select oregano clone with high phenolic compounds and then distilled to remove all the essential oil.27 The antimicrobial action of the oregano extract is attributed
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mostly to abundant water-soluble phenolic compounds.33 The leaf extract contains phenolic compounds such as rosmarinic acid, caffeic acid as well as flavonoids including epicatechin or quercetin giving it antioxidant, antimicrobial, antifungal, and anti-inflammatory activity without the irritating and sensitizing chemicals.33,34 Removing the essential oil is an important step, because the essential oils have been increasingly reported to cause allergic contact dermatitis.28-32 This oregano water-soluble extract has been shown to be effective against gram-positive and gram-negative microorganisms as well as mold and some yeast (data not shown).
The results of this pilot study demonstrate that oregano extract ointment was an effective antimicrobial ointment for wound healing. The oregano ointment group had fewer positive bacterial cultures for S. aureus, 19 percent versus 41percent, and fewer acute infections, 6 percent versus 16 percent, compared with the petrolatum group. While the petrolatum infection rate appears higher than typically reported in the literature, it is similar to 17.6 percent seen in the petrolatum group in the article by Dire, et al,11 and is limited by the small sample size and inter-resident surgeon variability. Another finding that deserves attention is the high colonization rate seen in the petrolatum group, which indicates a need for further evaluation, but may partially be contributed to the high nasal colonization rates that currently exist in the general population.37 Overall, oregano ointment was effective at reducing bacterial contamination of the excision site at day 12, which resulted in a reduction of acute infections. Although these numbers were not statistically significant, a clinically important trend is observed which highlights the need for larger clinical trials involving water soluble oregano extract ointment on wound healing.
In regards to scar assessment, this study used a validated scar assessment tool known as the Patient and Observer Scar Assessment. 35, 36 Pigmentation in the physician assessment is similar to the color category in the patient assessment. A statistically significant improvement in the oregano group compared to the petrolatum group occurred in both the physician and patient scar assessment of pigmentation and color, which highlights the consistency between the physician and patient scar assessment scores. While all the oregano scores on day 90 were lower (closer to normal skin) in the physician scar assessment, only pliability reached a statistically significant difference. Therefore, the oregano ointment group was essentially equivalent to petrolatum, the current standard, post-operative ointment, in regards to scar assessment.
These results are promising, despite the limitations of a small sample size and a single center. Another limitation of this study is that different resident physicians were performing the excision and thus inter-surgical variability and experience could play a role in the scar outcome and infection rate.
Oregano ointment was well tolerated by the study group without significant adverse reactions. Further large-scale, ran-