Fentanyl transdermal patches induced chemical leucoderma.

Chemical leucoderma is defined as hypopigmentation or vitiligo-like hypomelanosis caused by repeated chemical exposure, and the diagnosis can be made clinically. Chemical leucoderma induced by fentanyl transdermal patches is rare. This case report involves a 53-year-old man with chronic back pain caused by herniated nucleus pulposus at the L4-L5 level. The patient had used fentanyl transdermal patches for about 2 years. Depigmented lesions were observed in the areas where fentanyl transdermal patches had been applied. Chemical leucoderma was the most likely diagnosis. There remains a debate regarding whether there is a fentanyl dose-response relationship and whether the duration of exposure is relevant. Spontaneous repigmentation may occur after discontinuing the chemical exposure, and follow-ups are recommended to monitor whether spontaneous repigmentation occurs. Additionally, several treatment options have been proposed as specific treatments for chemical leucoderma, including psoralens, corticosteroids, calcineurin inhibitors, immunosuppressive agents and phototherapy.