The effects of onion extract on hypertrophic and keloid scars

J Wound Care. 2007 Jun;16(6):251-4. doi: 10.12968/jowc.2007.16.6.27070.


Objective: To evaluate the therapeutic activity of topical onion extract in gel form on hypertrophic and keloid scars, focusing on problems such as elevation, redness, hardness, itching and pain.

Method: This comparative prospective study assigned 60 patients to three groups. Group I was treated with onion extract alone, group 2 with silicon gel sheet alone and 3 group with a combination of onion extract and silicon gel sheet.

Results: In the group comparisons, a significant difference was observed at the end of six months in the colour parameter between group I and group 2 and in the height parameter between group I and group 3 (ANOVA post-hoc Tukey's test, p<0.01 and p<0.05 respectively). The onion extract was more effective in relation to scar colour, while the silicon gel sheet was superior in decreasing the height of scar (paired sample t-test, p<0.001). In addition, the most effective therapeutic results were obtained when the silicon gel sheet treatment was combined with onion extract in group 3.

Conclusion: Onion extract improved hypertrophic and keloids scars via multiple mechanisms. However, it was statistically ineffective in improving scar height and itching. For this reason, onion extract therapy should be used in combination with an occlusive silicon dressing to achieve a satisfying decrease in scar height.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Administration, Topical
  • Adult
  • Allantoin / administration & dosage
  • Allantoin / therapeutic use*
  • Cicatrix, Hypertrophic / drug therapy*
  • Drug Combinations
  • Female
  • Gels
  • Heparin / administration & dosage
  • Heparin / therapeutic use*
  • Humans
  • Keloid / drug therapy*
  • Male
  • Middle Aged
  • Phytotherapy
  • Plant Extracts / administration & dosage
  • Plant Extracts / therapeutic use*
  • Prospective Studies
  • Silicones / administration & dosage
  • Silicones / therapeutic use
  • Time Factors
  • Treatment Outcome


  • Drug Combinations
  • Gels
  • Plant Extracts
  • Silicones
  • allantoin, heparin, onion extract drug combination
  • Allantoin
  • Heparin