A novel presentation of minocycline-induced nail discoloration: A case report.

Minocycline, a tetracycline antibiotic used to treat acne and rosacea, is known to cause nail discoloration, typically as blue-gray pigmentation. However, other unique manifestations are less frequently reported. A 19-year-old male with acne developed a unique 'snow mountain nail' after one month of minocycline treatment. The patient's nails showed blue-gray pigmentation near the nail bed, along with bright white changes at the free edge and parallel white stripes on the nail bed, forming a distinctive dual-color pattern. After the discontinuation of minocycline, the treatment plan was also adjusted. After 2 months, the pigmentation was significantly reduced. After 2 years the nails had returned to normal and there were no residual pigmented spots. The 'snow mountain nail' phenomenon introduces a novel clinical presentation of minocycline-induced pigmentation. It may be proposed that minocycline forms chelates with iron, which accumulate in the nail cuticle, causing discoloration. The bright white stripes may result from changes in the blood supply or inflammation in the nail bed. This case expands the understanding of minocycline-induced nail discoloration, emphasizing the importance of early recognition and management of this side effect to minimize its cosmetic and psychological impact. The present findings offer new insights into its pathogenesis and diagnostic significance.