Preventive Effect of Glycyrrhiza Glabra Extract on Oral Mucositis in Patients under Head and Neck Radiotherapy: A Randomized Clinical Trial

  • Shamsolmolok Najafi Assistant Professor, Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
  • Soraiya Ebrahimpour Koujan PhD Student, Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
  • Soheila Manifar Assistant Professor, Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
  • Mohammad Javad Kharazifard Epidemiologist, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Saba Kidi Dentistry Student, School of Dentistry, International Campus, Tehran University of Medical Sciences, Tehran, Iran
  • Samira Hajheidary Postgraduate Student, Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
Keywords: Mucositis, Glycyrrhiza, Radiotherapy, Mouth Neoplasms


Objectives: About two-thirds of cancer patients undergo radiotherapy. Oral mucositis represents a major complication of radiotherapy, causing morbidity and mortality and decreasing the quality of life of patients. This study aimed to assess the preventive effect of Glycyrrhiza aqueous extract on oral mucositis in cancer patients under head and neck radiotherapy.

Materials and Methods: In this double-blind clinical trial, 37 head and neck cancer patients were divided into intervention (n=19) group receiving Glycyrrhiza aqueous extract and control (n=18) group receiving placebo. Patients in the test group used Glycyrrhiza aqueous extract topically twice a day from the first day of starting radiotherapy until the end of the second week. Patients were examined in the first day of radiotherapy for any type of wound before treatment and those with oral ulcers before radiotherapy were excluded from the study. The grade of mucositis was determined using the classification by the World Health Organization. ANCOVA was performed to assess any difference between the two groups with regard to oral mucosal irritation and wound size after the intervention while controlling for the covariates such as sex and age.

Results: Significant differences were found in the maximum grade of mucositis and oral mucosal irritation between the intervention and control groups (P<0.001).

Conclusions: This study showed that aqueous extract of Glycyrrhiza can be effective for decreasing the severity of oral mucositis in head and neck cancer patients undergoing radiotherapy.


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How to Cite
Najafi S, Ebrahimpour Koujan S, Manifar S, Kharazifard MJ, Kidi S, Hajheidary S. Preventive Effect of Glycyrrhiza Glabra Extract on Oral Mucositis in Patients under Head and Neck Radiotherapy: A Randomized Clinical Trial. Front Dent. 14(5):267-274.
Original Article

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