Discolouration of the fingernails from using hydroquinone skin-lightening cream.

A 23-year-old left-handed white male was referred with a complaint of brown discolouration of the fingernails of his left hand. He had been applying 4% hydroquinone cream to facial melasma. The discolouration began in winter and worsened in March and April. It resolved within 2 months of cessation of hydroquinone. There are only a few reports of nail staining as a result of hydroquinone in the literature. Nail discolouration as a result of hydroquinone may occur on only one hand.