Unilateral Linear Lichen Planus Pigmentosus Responding to Isotretinoin: A Case Report.

Lichen planus pigmentosus (LPP) is a rare variant of lichen planus. Due to the scarce number of patients diagnosed with LPP, there are no treatment guidelines. Multiple topical and oral agents are utilized in LPP with varying degrees of response. Isotretinoin has only been investigated in a case report and a single prospective pilot study for managing LPP. Herein, we report the efficacy, safety, and moderate improvement of LPP patients on isotretinoin 20 mg (0.25 mg/kg), topical adapalene gel, 4% hydroquinone cream, and topical sunscreen.