Melasma can be a very frustrating, remitting, and relapsing condition, particularly in the summer months. Often patients get good results with at-home and in-office treatments and return frustrated as the melasma frequently recurs. A thorough history can help identify melasma triggers.
Ask about exposure to:
1. Any heat source. You will be surprised by the answers. Examples include overhead work lights, overhead desk lamps, extensive cooking over an oven or a grill, lamps used to treat seasonal affective disorder, heating lamps, and hair dryers. Heat is a very common trigger for melasma as it increases vasodilation. Melasma is typically thought of as solely hyperpigmentation; however, vascular dilatation often occurs in the affected area. In addition, heat may lead to more inflammation, also stimulating melanocyte pigment production.
2. UV sources. These include computer screens, car side windows, sunroofs (even if the roof glass is closed, UV can penetrate the glass, so the sunroof shade also should be closed), and a window near an office desk or a window near a bed (UVA penetrates window glass).
3. Visible light sources. Examples are overhead lights at home and in office buildings. These lights increase pigmentation. Iron oxide in sunscreens helps block visible light.
4. Hormonal triggers. These include birth control pills, hormone-releasing intrauterine devices, hormone therapy, and vitamin supplements such as those used for pregnancy, nursing, and perimenopausal symptoms (such as black cohosh and dong quai).
5. Other triggers:• Scented or deodorant soaps, toiletries, cosmetics, or fragrances that may cause phototoxic reactions. These reactions may in turn trigger melasma, which may then persist.
• Sunglasses. This is the most common avoidable trigger. Aviator sunglasses or sunglasses with metal rims, or metal attached to the inside handle or rim absorb the heat when in the sun and/or when left in the car. The metal gets warm, and the heat transfers to the skin when the sunglasses are placed on the face. I ask every melasma patient to bring in all their sunglasses so I can check for metal on the rim or handles. This is a very common trigger, and patients are shocked after they observe that streaks of melasma can often follow the pattern of their sunglasses.
• Autoimmune thyroid disorders, chronic stress, or adrenal dysfunction.
• Triggers of melanocyte-stimulating hormone.
The history is crucial to long-term clearance of melasma. Asking questions to get to the source of the trigger often can help isolate the cause and help eliminate significant recurrences of melasma in skin of color patients.
Dr. Wesley and Dr. Talakoub are cocontributors to a monthly Aesthetic Dermatology column in Dermatology News. Dr. Talakoub is in private practice in McLean, Va. Dr. Wesley practices dermatology in Beverly Hills, Calif. This month's column is by Dr. Talakoub.