“…Tranexamic acid has also been reported to have biochemical/physiological behavior that needs further investigation. When tranexamic acid was applied topically to the entire facial area, it lightened areas of melasma, but not other pigmented areas such as senile lentigo or freckles [1]. Also, in two other studies in humans, in one study it increased levels of occludin, the tight junction protein important in epithelial barrier formation [11], but in a second study, it failed to increase levels of collagen IV, the biomarker for basement membrane integrity, to those seen in normal skin [4].…”