Objective: Acne vulgaris is one of the most common skin disorders, and oral isotretinoin has widely been used as a treatment for severe and resistant cases in recent years. This article considers the controversy over systemic isotretinoin's effect on the serum level of folic acid and its implications for health.
Methods: This study was conducted to assess the effect of systemic isotretinoin on the serum level of folic acid. Sixty-one patients, including 38 women and 23 men (mean age 23.6 6 years) with severe or moderate acne that was resistant to conventional treatments, were supplemented with 0.5 mg/kg/d of oral isotretinoin for 30 days. They were instructed not to use any other drugs having an effect on the folic acid level nor change their diet. The serum levels of folic acid were measured at the baseline and at the end of the treatment period. Statistical analyses were carried out using the paired t test.
Results: Mean levels of folic acid were 26.75 9.42 nmol/L at baseline, and and 23.6 8.42 nmol/L after 30 days of isotretinoin supplementation. This showed a significant decrease in the serum level of folic acid (P=.008).
Conclusion: Given the significant decrease in the serum level of folic acid following a 30-day use of oral isotretinoin in acne patients, and considering the important role of folic acid in metabolic functions, we recommend further studies to assess the effect of longer periods of isotretinoin treatment, in addition to studies including other relevant factors in folic acid metabolism (e.g., serum homocysteine levels). Moreover, folic acid supplementation in acne patients using isotretinoin is recommended.