What should you know about nail bed thickening?

A thick nail may become hard to trim, yellow or dull, curved, ridged, crumbly, or partly detached. The change can affect a toenail or fingernail and may develop slowly after repeated pressure or trauma. Fungal nail infection and nail psoriasis can look similar, while some changes reflect altered nail growth rather than infection. A clinician considers the pattern, surrounding skin, footwear, injuries, and other symptoms.

Do not force thick nails into tight shoes or cut deeply beneath them. Trim carefully after bathing, file sharp edges, and keep tools clean. Choose footwear with enough room for the toes. A clinician may take a nail sample before antifungal medicine is used. Depending on the cause, care can include treatment for nail fungus, an oral antifungal medicine, or another plan for inflammation or pressure.

Arrange an examination when thickening is painful, spreading, recurrent, or affecting walking. Seek prompt care for drainage, increasing warmth, spreading redness, fever, a wound beneath the nail, or a dark mark that does not grow out. Earlier assessment is sensible if diabetes, poor circulation, or reduced foot sensation makes minor injuries harder to notice.

What is the likely cause of this thickening? Should the nail be tested for fungus? Could footwear or an old injury be contributing? How should I trim it safely? Which treatment is appropriate, and what changes require review?