title: Influence of vitamin C on the elicitation of allergic contact dermatitis to p-phenylenediamine.
abstract: BACKGROUND
  Hair dyes represent one of the most important causes of allergic contact dermatitis resulting from the use of cosmetic products. The principal causative chemistry is associated with oxidation products of p-phenylenediamine (PPD) and closely related substances.
  
  
  OBJECTIVE
  To examine whether prior application of the antioxidant vitamin C to the skin was able to reduce the cutaneous allergic response to PPD.
  
  
  METHODS
  Twenty eight volunteers with a proven history of contact allergy to PPD were recruited. Each was tested with a range of PPD doses and PPD-containing hair dye on untreated skin and skin pretreated for 10 min with a vitamin C formulation.
  
  
  RESULTS
  Pretreatment of skin sites with vitamin C led to a reduction in the intensity, or even ablation, of the cutaneous allergic reaction to PPD in ∼75% of cases as compared with untreated skin.
  
  
  CONCLUSIONS
  The results suggest that treatment of the skin adjacent to the hair-bearing area with antioxidant could form part of a strategy to reduce the burden of cosmetic allergic contact dermatitis caused by hair dyeing.
authors.affiliation: HDS Ltd, Sharnbrook, MK44 1PR, UK.
authors.forename: David A
authors.initials: DA
authors.lastname: Basketter
authors.affiliation: HDS Ltd, Sharnbrook, MK44 1PR, UK.
authors.forename: Ian R
authors.initials: IR
authors.lastname: White
authors.affiliation: Institute of Dermatology, Bangkok, 10400, Thailand.
authors.forename: Preya
authors.initials: P
authors.lastname: Kullavanijaya
authors.affiliation: Institute of Dermatology, Bangkok, 10400, Thailand.
authors.forename: Poohglin
authors.initials: P
authors.lastname: Tresukosol
authors.affiliation: Institute of Dermatology, Bangkok, 10400, Thailand.
authors.forename: Mingkwan
authors.initials: M
authors.lastname: Wichaidit
authors.affiliation: HDS Ltd, Sharnbrook, MK44 1PR, UK.
authors.forename: John P
authors.initials: JP
authors.lastname: McFadden
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use*; D004396:Coloring Agents / Q000008:administration & dosage*; D017449:Dermatitis, Allergic Contact / Q000209:etiology / Q000517:prevention & control*; D006202:Hair Dyes / Q000009:adverse effects*; D006801:Humans; D010328:Patch Tests; D010655:Phenylenediamines / Q000009:adverse effects*; D011292:Premedication / Q000379:methods; D012720:Severity of Illness Index
chemical_list: D000975:Antioxidants; D004396:Coloring Agents; D006202:Hair Dyes; D010655:Phenylenediamines; D001205:Ascorbic Acid; C029728:4-phenylenediamine
keywords: allergy reduction; antioxidant; ascorbic acid; hair dye; p-phenylenediamine; vitamin C