en تخصصي Special پژوهشي Research Objective: This study aimed to estimate the prevalence of lichenoid reactions to Anti Hyperglycemic Agents. Materials and Methods: In this cross-sectional descriptive and analytic study, we examined the oral mucosa of 411 patients at the age of 29 to 85 in 3 groups who consumed various antihyperglycemic agents. Results: In overall, 31 patients had lichenoid reactions (12 patients taking glibenclamide, 1 patient taking metformin and 18 patients taking glibenclamide with metformin) and there was a significant difference between the groups (P = 0.013). The most of the lesions were at the age's upper than 60 years. From 31 patients with lichenoid reactions, 14 subjects (45%) were male and 17 subjects (55%) were female. Conclusion: Prevalence of lichenoid reactions in this study was 7.5% approximately. By considering the significant difference among the groups in the incidence of lesions, the significant effect of glibenclamide in inducing lichenoid reactions can be considared. Diabetes mellitus; Lichenoid reactions; Glibenclamide; Metformin 77 82 http://ijdo.ssu.ac.ir/browse.php?a_code=A-10-30-49&slc_lang=en&sid=1 Hakimeh Ahadian No Department of Oral Medicine, Shahid Sadoughi University of Medical Science, Yazd, Iran Samira Hajimaghsoodi Yes Department of Oral Medicine, Shahid Sadoughi University of Medical Science, Yazd, Iran Mohammad Afkhami-Ardekani No Yazd Diabetes Research Center, Shahid Sadoughi University of Medical Science, Yazd, Iran