Melanonychia: Understanding Nail Discoloration

What is Melanonychia?

Melanonychia is a condition that causes brown or black lines or streaks to appear on the nails. It can affect both fingernails and toenails, and may appear in a single nail, a few nails, or all of them.

Types of Melanonychia

There are three main types of melanonychia:

• Longitudinal Melanonychia: Brown or black lines that run parallel to the nail bed.
• Transverse Melanonychia: Brown or black lines that cross the nail horizontally.
• Diffuse Melanonychia: Generalized darkening of the entire nail.