title: Allergic reactions to tattoo pigment after laser treatment.
abstract: BACKGROUND
  Cutaneous allergic reactions to pigments found in tattoos are not infrequent. Cinnabar (mercuric sulfide) is the most common cause of allergic reactions in tattoos and is probably related to a cell-mediated (delayed) hypersensitivity reaction.
  
  
  OBJECTIVE
  The purpose of these case presentations is to describe a previously unreported complication of tattoo removal with two Q-switched lasers.
  
  
  RESULTS
  Two patients without prior histories of skin disease experienced localized as well as widespread allergic reactions after treatment of their tattoos with two Q-switched lasers.
  
  
  CONCLUSIONS
  The Q-switched ruby and neodymium:yttrium-aluminum-garnet lasers target intracellular tattoo pigment, causing rapid thermal expansion that fragments pigment-containing cells and causes the pigment to become extracellular. This extracellular pigment is then recognized by the immune system as foreign.
authors.affiliation: Ronald O. Perelman Department of Dermatology, New York University School of Medicine, New York 10016, USA.
authors.forename: R
authors.initials: R
authors.lastname: Ashinoff
authors.forename: V J
authors.initials: VJ
authors.lastname: Levine
authors.forename: N A
authors.initials: NA
authors.lastname: Soter
mesh_terms: D000328:Adult; D003876:Dermatitis, Atopic / Q000209:etiology*; D005260:Female; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects*; D007866:Leg; D010860:Pigments, Biological / Q000009:adverse effects*; D013653:Tattooing
chemical_list: D010860:Pigments, Biological