Background: Acne vulgaris is the most common inflammatory skin disease. It is primarily observed in adolescents and is characterized by comedones, papules, pustules, nodules, and cysts on the face, back, chest, chin, and body skin. Acne vulgaris affects about 80% of teenagers and continues beyond the age of 25 years in 3% of men and 12% of women in the world. Isotretinoin is one of the most common treatment agents for acne vulgaris, which causes oxidative DNA damage in the cell. As an important indicator of oxidative DNA damage, 8-hydroxy-2’-deoxyguanosine is repaired with an enzyme called human 8-oxoguanine DNA glycosylase 1 (hOGG1). Objectives: We aimed to evaluate oxidative DNA damage in acne vulgaris before and after isotretinoin treatment by measuring the 8-OHdG and hOGG1 levels. Methods: The 8-OHdG and hOGG1 levels were evaluated from serum samples using the enzyme-linked immunosorbent assay (ELISA) method. Both the serum 8-OHdG (P < 0.05; P < 0.0001) and hOGG1 (P < 0.05; P = 0.04) levels were found to be statistically higher in the sixth month after isotretinoin treatment. Results: In this first report, the 8-OHdG and hOGG1 levels were found to be statistically significantly high after isotretinoin treatment. According to our results, the 8-OHdG level increased under isotretinoin administration in acne vulgaris patients. Conclusions: Consequently, healing via hOGG1 likely continues after dropping isotretinoin for DNA.