title: Photodynamic therapy for psoriasis.
abstract: BACKGROUND
  Photodynamic therapy for psoriasis showed promise in the early 1990s with reports of plaque clearance following topical aminolevulinic acid - photodynamic therapy (ALA-PDT).
  
  
  METHODS
  In December 2013, we conducted a systematic search of the PubMed Medline database using the keywords "psoriasis" and "photodynamic therapy".
  
  
  RESULTS
  Numerous clinical studies have failed to demonstrate a consistent, efficacious response to topical ALA-PDT. Furthermore, severe pain and burning sensations were repeatedly reported, many cases being intolerable for patients.
  
  
  CONCLUSIONS
  The variability in clinical response and the painful side effects have made topical ALA-PDT an unsuitable treatment option for chronic plaque psoriasis. Nonetheless, early clinical studies of other modalities such as topical hypericin and methylene blue, as well as systemic ALA and verteporfin, have shown that these photosensitizers are efficacious and much better tolerated than topical ALA.
  
  
  CONCLUSIONS
  With the current landscape of phototherapy dominated by psoralen combined with ultraviolet A (PUVA) and narrow-band ultraviolet B (NB-UVB), an alternative light therapy utilizing the visible spectrum is certainly promising and a worthwhile endeavor to pursue.
authors.affiliation: David Geffen School of Medicine , UCLA, Los Angeles, CA , USA and.
authors.forename: Young M
authors.initials: YM
authors.lastname: Choi
authors.forename: Lily
authors.initials: L
authors.lastname: Adelzadeh
authors.forename: Jashin J
authors.initials: JJ
authors.lastname: Wu
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D000873:Anthracenes; D006801:Humans; D010569:Perylene / Q000008:administration & dosage / Q000031:analogs & derivatives; D010778:Photochemotherapy / Q000009:adverse effects / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D011166:Porphyrins / Q000008:administration & dosage; D011565:Psoriasis / Q000188:drug therapy*; D000077362:Verteporfin
chemical_list: D000873:Anthracenes; D017319:Photosensitizing Agents; D011166:Porphyrins; D000077362:Verteporfin; D010569:Perylene; C004965:hypericin; D000622:Aminolevulinic Acid
keywords: ALA; PpIX; aminolevulinic acid; hypericin; methylene blue; verteporfin