How is the diagnosis of melasma made?

Examination: The increased color and distribution are the criteria for melasma. A special ultraviolet light, woods lamp, can help determine the depth of the pigment. Deeper pigment is more difficult but not impossible to treat. Blood tests or skin biopsy are not necessary for the diagnosis.

Melasma: Melasma is diagnosed through its visual signs & personal history. A dermatologist may look at your skin under a device called wood's light. In some cases, rarely melasma may look like another skin condition, in which case the dermatologist may perform a biopsy and send it to a lab for diagnostic evaluation.