Acanthosis nigricans (AN) is a chronic skin disorder that is characterized clinically by velvety darkening of the skin mainly at the back of the neck and also includes face, axilla, cubital fossa, knuckles and groin region. It is most commonly associated with diabetes and insulin resistance, or hormonal disorders, certain drugs such as steroids and oral contraceptives, and rarely internal malignancy. Thus, acanthosis nigricans is an indicator of metabolic syndrome in many diseases such as psoriasis, lichen planus, and atopic dermatitis.

Treatment is usually challenging. However, the condition usually improves by treating the cause as in the case of insulin resistance and weight loss. Other treatment modalities include keratolytics, such as topical retinoids (eg, topical tretinoin 0.1%), topical vitamin D analogues (eg, calcipotriol 0.005%), oral retinoids, octreotide, dermabrasion, and chemical peels with variable outcome.

In addition, various types of lasers have been used for managing AN as long-pulsed alexandrite laser, ablative carbon dioxide laser, fractional 1550-nm erbium fibre, and fractional CO2 laser with variable treatment results.

Fractional CO2 laser acts by fractionated photothermolysis by making skin columns of thermal injury known as micro-thermal zones. It improves the condition by removing thin layers of skin with minimal thermal damage leading to collagen injury and collagen remodelling. The latter helps in improving both the texture and thickness of the skin. In addition, transepidermal elimination of the dermal content is a possible mechanism by which the melanin is eliminated.

Tranexamic acid (TA) is an antifibrinolytic, reversibly binding to plasminogen, and thus preventing its conversion to plasmin and subsequent breakdown of fibrin. Additionally, TA reduces expression of vascular endothelial growth factor and endothelin-1, which also acts to minimize bleeding and hamper angiogenesis.

There remains a significant gap in comprehensive research focusing specifically on the combined efficacy of fractional CO2 laser therapy with tranexamic acid for treating AN. This study evaluates the need for fractional co2 and fractional co2 with tranexamic acid in acanthosis nigricans.