What Causes Nail Separation?

Onycholysis is a gap between the nail plate and the skin beneath it. The lifted part may look white, yellow, or grey because air enters the space. A common cause is [Nail Fungus](/conditions/nail-fungus/), which can thicken, discolour, and weaken the nail. [Nail Psoriasis](/conditions/nail-psoriasis/) can also create surface pits, debris, and lifting. A trapped splinter, manicure trauma, tight footwear, frequent immersion, detergents, or chemical exposure may separate a nail without infection. Several causes can overlap, so colour alone does not identify the cause.

Keep the nail short by filing loose edges rather than pulling them. Dry hands and feet carefully, wear protective gloves for wet or chemical work, and avoid picking, artificial nails, and aggressive manicures until the nail settles. Do not share nail tools. A clinician can examine the nail and, when needed, test material for fungus before choosing treatment. The detached section normally has to grow out as new nail forms, so protection and patience matter.

Book an assessment when separation is unexplained, affects several nails, keeps returning, or comes with thickening, pain, swelling, drainage, or a new dark streak. Seek prompt care if redness spreads into the finger or toe, or if you have diabetes, poor circulation, or reduced immunity.

Could this be fungal, inflammatory, traumatic, or related to a medicine? Would a nail sample help? How should I trim and protect the nail while it grows out?