title: Near-visible light and UV photoprotection in the treatment of melasma: a double-blind randomized trial.
abstract: BACKGROUND
  Melasma is an acquired hyperpigmentation on sun-exposed areas. Multiple approaches are used to treat it, but all include broad ultraviolet (UV)-spectrum sunscreens. Visible light (VL) can induce pigmentary changes similar to those caused by UV radiation on darker-skinned patients.
  
  
  OBJECTIVE
  To assess the efficacy of sunscreen with broad-spectrum UV protection that contains iron oxide as a VL-absorbing pigment (UV-VL) compared with a regular UV-only broad-spectrum sunscreen for melasma patients exposed to intense solar conditions.
  
  
  METHODS
  Sixty-eight patients with melasma were randomized in two groups to receive either UV-VL sunscreen or UV-only sunscreen, both with sun protection factor ≥ 50, over 8 weeks. All patients received 4% hydroquinone as a depigmenting treatment. At onset and at conclusion of the study, they were assessed by the Melasma Activity and Severity Index (MASI; a subjective scale), colorimetry (L*) and histological analysis of melanin.
  
  
  RESULTS
  Sixty-one patients concluded the study. At 8 weeks, the UV-VL group showed 15%, 28% and 4% greater improvements than the UV-only group in MASI scores, colorimetric values and melanin assessments, respectively.
  
  
  CONCLUSIONS
  UV-VL sunscreen enhances the depigmenting efficacy of hydroquinone compared with UV-only sunscreen in treatment of melasma. These findings suggest a role for VL in melasma pathogenesis.
authors: Department of Dermatology, Hospital Central 'Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosi, Mexico.
authors: Juan Pablo
authors: JP
authors: Castanedo-Cazares
authors: Diana
authors: D
authors: Hernandez-Blanco
authors: Blanca
authors: B
authors: Carlos-Ortega
authors: Cornelia
authors: C
authors: Fuentes-Ahumada
authors: Bertha
authors: B
authors: Torres-Álvarez
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008027:Light; D008548:Melanosis / Q000188:drug therapy* / Q000517:prevention & control; D013473:Sunscreening Agents / Q000627:therapeutic use*; D016896:Treatment Outcome; D014466:Ultraviolet Rays
chemical_list: D013473:Sunscreening Agents
keywords: iron oxide; melasma; photoprotection; sunscreens; visible light