My big toenail is lifting off: what should I know?

Nail separation may begin after a stubbed toe, pressure from tight shoes, repeated moisture, or picking beneath the nail. A thickened or yellow nail with crumbly material can occur with nail fungus. Pits, ridges, or separation in more than one nail can occur with nail psoriasis. The exposed space can collect moisture and debris, which may encourage secondary infection.

The detached portion usually does not reattach to the nail bed. Healthy nail must grow forward from the base, so improvement is gradual and depends on the cause.

Keep the toe clean and dry, wear shoes with room at the toes, and trim only loose edges with clean clippers if they catch. Do not tear the nail off or push tools underneath it. Protect a tender edge with a light dressing that is changed when damp, and avoid swimming or shared nail tools until infection has been considered.

Book an assessment if the nail remains lifted, changes colour, or affects walking. A clinician can examine the nail and may test material before recommending treatment; nail surgery is reserved for selected problems and is not a routine first step.

Seek prompt care for spreading redness, warmth, swelling, pus, worsening pain, fever, or a dark mark that does not follow a clear injury. People with diabetes, poor circulation, or reduced immunity should arrange assessment early for any open or infected toe.

Could this be trauma, nail fungus, or nail psoriasis? Should the nail be tested? How should I trim or dress it, and what signs would suggest infection?