It works from the sides of the darkened area to the center until it goes away. It effectively prevents darkening of the skin due to sun exposure and aging. TXA also lightens the pigmentation of acne, scars, sun overexposure, and skin spots related to medications and hormonal changes

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Tranexamic acid is a synthetic analog of the amino acid lysine and used as an antifibrinolytic that competitively inhibits the activation of plasminogen to plasmin. In melasma - Tranexamic acid has shown to provide rapid and sustained lightening in melasma by decreasing melanogenesis in epidermal melanocytes.

Tranexamic acid is widely used in Brazil as a tailor-made option for the treatment of hyperpigmentation. In more than 5 years of its off label use, only reported positive results.

But whether it has any carcinogenic effect should be studied.