Why am I suddenly experiencing a dark brown spot appearing on my fingernail?

Why am I suddenly experiencing a dark brown spot appearing on my fingernail?

1. Introduction A sudden dark brown spot on a fingernail is most often a subungual hematoma, which is a collection of blood trapped beneath the nail plate following localized physical trauma. However, a persistent, painless dark streak or spot that expands must be clinically evaluated to rule out subungual melanoma, a rare but serious form … Read more