Tranexamic acid is an off-label use (i.e. not an officially approved indication) oral medication for the treatment of melasma not responding to topical lightening agents. Its use for melasma treatment has been largely confined to Asia.
The usual dose is 250mg (half a 500mg tablet) twice daily for 12 weeks. It is effective in up to 80% of patients. Most patients achieve significant lightening of melasma (usually 50-75% lightening) after about 4-6 weeks of usage.
Maintenance topical therapy using various lightening agents and strict sun protection is recommended after the oral tranexamic acid is stopped to sustain the lightening benefits.
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