Hi,
Melasma is best considered as a "chronic" pigmentary condition affecting the skin.
As such, the key treatment objective should be to "control" the pigmentation rather than to "cure" the condition.
Sun avoidance/protection and the use of effective proven skin lightening agents should be the mainstay of treatment.
Chemical peeling such as Cosmelan peel helps remove superficial melasma by the process of accelerated skin renewal.
Lasers help by dispersing the melasma pigments.
Both strategies should be considered as 2nd/3rd line therapies when topical treatment fails to achieve satisfactory results.
As a word of caution, results of these treatment options may be variable, worsening of melasma may occur and relapses often occur even if you experience initial treatment success.
Do see your doctor for a full assessment and a discussion if you are a suitable candidate for these treatment options.
Hope this explanation helps you understand the roles of chemical peeling and lasers in the treatment of melasma!
