From the FDA Drug Label
Topical application of hydroquinone produces a reversible depigmentation of the skin
- Reversibility of melasma is implied through the use of hydroquinone, which causes reversible depigmentation of the skin.
- The fact that exposure to sunlight or ultraviolet light will cause repigmentation of bleached areas suggests that melasma can recur after treatment.
- Based on the information provided, it appears that melasma can be reversible with treatment, but repigmentation can occur with exposure to sunlight or ultraviolet light 1
From the Research
Melasma is partially reversible with proper treatment and sun protection, though complete reversal is challenging. The most recent and highest quality study, published in 2022 2, suggests that combination therapies, either in double or triple combinations, yield the best results when compared to single therapies. First-line treatments include topical agents like hydroquinone (2-4%), applied once or twice daily for 8-12 weeks, often combined with tretinoin (0.025-0.1%) and a mild corticosteroid in what's called a triple combination cream. Azelaic acid (15-20%), kojic acid, vitamin C, and tranexamic acid are effective alternatives. Chemical peels containing glycolic acid or salicylic acid can enhance results when performed every 3-4 weeks. Laser treatments, such as the LFQS laser and picosecond laser, may help in resistant cases, as shown in a study published in 2020 3. Some key points to consider when treating melasma include:
- Strict sun protection is absolutely essential—use broad-spectrum SPF 30+ sunscreen daily, reapply every 2 hours when outdoors, and wear wide-brimmed hats and sun-protective clothing.
- Melasma often recurs with sun exposure because it results from melanocyte overactivity triggered by UV radiation, hormones, and genetic factors.
- Even with successful treatment, maintenance therapy and continued sun avoidance are necessary to prevent recurrence, as melanocytes remain sensitive to stimulation.
- Treatment choice should be made after Wood's lamp examination, as well as dermatoscopic evaluation, in order to select the best treatment option, targeted at each melasma subtype, as recommended in the 2022 study 2.