Melasma Is an acquired, chronic, recurrent, symmetrical hypermelanosis, which is characterized by brown patches of variable darkness on sun exposed areas of the body. It is more common in women. It is common psychologically and emotionally distressing cosmetic problem in affected patients .

Many studies examined multiple treatment options for melasma , but none of them is completely satisfactory with recurrence in most cases.

Tranexamic acid is is a relatively new drug for melasma . It is currently used via a spectrum of delivery routes including oral, topical, intradermal, and microneedling .

Laser-assisted drug delivery (LADD) is a technique that facilitates the delivery of topical medications .

On reviewing the previous literatures, few studies have focused on therapeutic effects of combined laser and TXA (topical and intradermal) in melasma, with variations in parameters of laser, in dose, concentration, form and routes of TXA application; and in follow up duration. These studies revealed variable unproven results, and since melasma is a challenging disease, additional studies are needed to determine the optimal laser parameters and the best absorbable topical TXA formula, ensuring the best efficacy and less complications.

To the best of our knowledge, this is the first study that will use topical TXA gel as an additive effect between sessions, and to confirm the effect of laser and TXA by histopathology and immunohistochemistry.

Inclusion Criteria:

• - Gender: Only female patients.
• Age: 18-50 years old.
• Type of melasma: Bilateral symmetrical facial melasma of all types.
• Fitzpatrick skin phototypes: Types III, IV and V.

Exclusion Criteria:

• - Pregnancy and lactation.
• Patients taking oral contraceptive pills, hormonal replacement therapy or isotretinoin at the time of the study or during the past 6 months. Concomitant use of anticoagulants, bleeding disorders.
• Scarring and keloid tendency, active skin infections, active HSV, and those with facial cancer.
• History of photosensitivity or photosensitizing medications such as sulfonamides and tetracycline.
• Previous history of post inflammatory hyperpigmentation.