Onion doesn't top petrolatum for wound-healing

November 1, 2005

Atlanta — A common and inexpensive petrolatum-based scar treatment emollient was as good as more expensive, heavily marketed onion extract over-the-counter topicals, according to a new study.

There are many over-the-counter and some prescription products being marketed for the treatment of scars. Yet, there are not any that have been clearly proven to be superior to petrolatum-based emollients, according to senior author S. Brian Jiang, M.D., medical director of the Dermatology and Laser Center, Beth Israel Deaconess Medical Center, Boston, and clinical instructor in dermatology at Harvard Medical School, Boston.

"Because many of our patients have asked about this product and because we have found no good data demonstrating this gel's efficacy, we conducted this study to compare Mederma to Aquaphor (Smith & Nephew), a much less expensive petrolatum-based ointment used in our clinxic as standard treatment for surgical wounds," Dr. Chung says.

Study particulars

The researchers studied 24 participants with new surgical wounds, post-Mohs or excisional surgeries.

Researchers divided each scar into two halves, treating one half with Mederma and the other half with Aquaphor, a petrolatum emollient.

During the first weeks post surgery until suture removal, participants received regular postoperative care and either a petrolatum-based gel or topical antibiotic. Subsequently, scars were treated with the onion extract and petrolatum emollients.

Research findings

At two weeks, 21 percent of the subjects did better with the onion extract, 33 percent did better with petrolatum and 46 percent showed no difference. At eight weeks, 18 percent of the scars treated with onion extract appeared better, 27 percent with the petrolatum and 55 percent showed no difference. At 12 weeks, 7 percent did better with onion extract, 7 percent did better with petrolatum and 86 percent showed no difference.

Differences between remedies

"There were no statistical differences between the petrolatum side and onion extract side when it came to redness, thickness, pruritus, burning or pain," Dr. Jiang tells Dermatology Times.

The authors conclude that for new surgical scars, in older Caucasian patients, the onion extract-based emollient did not improve overall cosmesis or symptomatology when compared to the petrolatum-based ointment, which is the less expensive of the two.

"Because I am a Mohs surgeon whose patient population is similar to the one we studied (median age of 65), I recommend that patients use the less expensive petrolatum," Dr. Jiang says. "However, you can only base conclusions on the patient population and specific characteristics of the scar in the study. One cannot generalize our results, based on this study alone, to a pediatric population, nonsurgical scars, non-Caucasians, etc."