Question - Topical hydroquinone is often used in the treatment of melasma, a common acquired skin condition that is characterized by symmetric, irregular brown or grayish brown patches on sun exposed areas. What permanent adverse effect may be seen in association with the use of the topical hydroquinone?
Answer - Permanent depigmentation, also known as leukoderma, has been reported in association with the topical application of hydroquinone. (Jow T and Hantash BM. Hydroquinone-induced depigmentation: Case report and review of the literature. 2014 Dermatitis 25(1): e1-e5. DOI: 10.1097/01.DER.0000438425.56740.8a)