Topical tacrolimus significantly promotes repigmentation in idiopathic guttate hypomelanosis: a double-blind, randomized, placebo-controlled study


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P. Rerknimitr. E-mail:


Background  Idiopathic guttate hypomelanosis (IGH) is an idiopathic disorder affecting a large number of people. Effective treatments are not yet available.

Objectives  To investigate the efficacy of topical 0.1% tacrolimus ointment compared with placebo in the treatment of IGH.

Materials and methods  Twenty-six patients were included in the study. Lesions on one side of the body were selected to have a treatment with 0.1% tacrolimus ointment, whereas those on the other side served as a control with placebo ointment that had the same physical appearance. Colorimeter was used to assess skin colour at baseline and at 1, 2, 3, 4 and 6 months of treatment.

Results  Mean luminosity scale after adjusted for baseline from the treated side gradually decreased and reached statistical significance compared with the control group after 6 months of treatment (P = 0.019). Physicians’ improvement grading score showed that 11% of the patients demonstrated improvement of their skin lesions on the treated side after 6 months’ treatment.

Conclusion  Topical 0.1% tacrolimus ointment appeared to be an effective and safe treatment for IGH. The improvements were best observed by colorimetry, yet, they were not statistically significant upon clinical assessments.