Till today, there is a clear evidence for massive H₂O₂/ONOO^- - mediated stress in the epidermal compartment of vitiligo. It has been demonstrated that this accumulation originates from numerous cellular (endogenous) and environmental sources. There are convincing results that these reactive species induce oxidation of many amino acids of various proteins/peptides which lead to structural modification, that can be a reason for partial or complete loss of functionality. It was shown that hydroquinone (HQ) has been utilised in topical preparations by Dermatologists in skin lightening and depigmentation of widespread vitiligo treatment. It was decided to investigate whether these patients exhibit quinone reduction via dicarbonyl xylulose reductase (DCXR) as this enzyme reduces quinones and xenobiotics. The results show that DCXR is markedly decreased and affected by H₂O₂ and ONOO^-. The results were demonstrated by utilising in situ immunofluorescence labelling, Western blot, and FT- Raman spectroscopy.