BACKGROUND: Melasma is a chronic, often relapsing skin disorder, with poor long-term results from all current therapies.Q switched 1064nm Nd:YAG laser and intradermal tranexamic acid both showed efficacy on the treatment of melasma. However, no combination therapy of both be reported.

OBJECTIVES: To compare the efficacy of low influence Q switched 1064nm Nd:YAG laser and low influence Q switched 1064nm Nd:YAG laser combined with intradermal tranexamic acid injection for melasma.

METHODS: Twenty patients with melasma were included in a randomized controlled observer-blinded study with split-face design. Each side of the face was randomly allocated to either six session at two-week interval of low influence 1064 Nd:YAG laser (6 mm spot size, energy fluence 1.2 - 1.4 J/cm 2 at 10 Hz) or low influence 1064nm Nd:YAG laser combined with intradermal tranexamic acid injection.Complication Improvement of melasma was assessed by Melasma area severity index (MASI),physician's global assessment (PhGA), MELASQOL scale, patient's global assessment (PGA), and patient's satisfaction at baseline,6th week,10th week after first treatment and 3 months, and 6 months after last treatment.

Inclusion Criteria:

• patients > 20 years old with refractory melasma to topical treatment

Exclusion Criteria:

• History of keloid, active eczema, active acne in the face, history of facial eczema, photosensitivity, use of isotretinoin in the past 6 months, pregnancy, and high exposure to sunlight or UV light (UVA or UVB)