The objective of this study is to assess and compare the efficacy of tranexamic acid intradermal microinjection alone versus its combination with low power fractional CO2 laser in a sequential pattern.

In all participants one half of the face will be randomly assigned to low power fractional CO2 laser while other side to Tranexamic acid intradermal microinjections on the 1st session. This split face session will be repeated every six weeks for 3 sessions.

In addition, Tranexamic acid intradermal microinjections will be applied for full face at the 2nd and 4th week of each split face session.

The response will be evaluated by the Melanin and erythema Indices which will be measured using reflectance spectrophotometer, Dermoscopy and photography before starting the study, two and four weeks after the last session. The sessions will take 4 months for each patient and another one month free of sessions for follow up.

Inclusion Criteria:

• Patients with bilateral symmetrical facial melasma

Exclusion Criteria:

• Pregnancy and lactation.
• Patients taking oral contraceptive pills or hormonal replacement therapy at the time of the study or during the past 12 months.
• Concomitant use of anticoagulants.
• Bleeding disorders.
• Personal or family history of deep venous thrombosis or thromboembolic events.
• Scarring and keloid tendency.
• Active skin infection, active Herpes simplex virus.
• History of Post-inflammatory hyperpigmentation.
• History of photosensitivity or photosensitizing medication as sulfonamides tetracycline,retinoids, bleaching creams, peeling and laser two months before the study.
• Occupational sun exposure.