25- 100mg a day for Melasma, however read the warnings.
Melasma can not be completely cured, however effective treatment are possible. This is because your skin is extremely sensitive to UV and even the smallest amount can stimulate your pigment cells to produce colour. The mainstay of treatment is strict UV protection- hats, sunglasses and SPF every 4 hours.
I prefer to use a combination of creams and laser for melasma. Hydroquinone can be used (5-8%), along with vitamin A creams. I usually start my patients on laser (low dose Q switch or Picosure) a few weeks after they commence on creams.
In some cases I combine glycolic AHA peels, and in other cases I use a tablet called Tranexamic acid to help. Dose is 50mg once a day. I know some dermatologist give 25 mg, some 100 mg. Be careful as blood clots have been associated with T. Acid and a screening history MUST be undertaken. All the best, Dr Davin Lim. Laser, surgical and aesthetic dermatologist. Brisbane, Australia