What Causes Diffuse Nail Discoloration, and How Can It Be Treated?

When you notice your nail turning a different color across most of its surface, it is called diffuse discoloration. One common cause is a fungal infection, known as onychomycosis, which can make nails look yellowish, brownish, and thick. Sometimes, an infection or inflammation around the nail (paronychia) can also change its color because of swelling or irritation. Pigment changes, like melanonychia, might give a different color to the nail although this often shows up as a band rather than affecting the whole nail. To decide how to treat it, a doctor may look at your nail and ask you questions about how long the color change has been there. They might do tests on a small scrap of nail to see if there is a fungus or another problem. Based on what they find, treatment might include using antifungal creams, or pills if a fungus is to blame. If the issue is from inflammation or another cause, different treatments may be recommended. Following your doctor’s advice and keeping your nails clean and protected are important steps to help your nails heal.