What should you know about nail psoriasis subungual hyperkeratosis?

Subungual means under the nail, while hyperkeratosis describes extra keratin. The nail may look lifted, yellow-white, thick, or packed with crumbly debris. A common presentation of nail psoriasis is this build-up beneath the nail, often alongside pits, ridges, colour change, or separation from the nail bed. A fungal infection and other nail disorders can look similar, so appearance alone cannot confirm the cause.

Keep nails trimmed without cutting into the corners, and do not dig under the plate or tear away lifted nail. Wear gloves for wet work and protect the fingertip from knocks. A clinician may soften surrounding thick skin with an emollient; see [Thickened Skin](/symptoms/skin-thickening/) and [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) for related information. Treatment directed at psoriasis may be needed, while removal of resistant material is a clinician procedure rather than a home task.

Arrange a dermatology assessment if the nail is changing, repeatedly lifting, painful, or difficult to clean. Seek prompt medical care for spreading redness, warmth, swelling, pus, fever, or bleeding after an injury. A sudden dark streak, a new isolated change, or pigment reaching the nearby skin also deserves assessment because not every nail change is psoriasis.

Could this be nail psoriasis, fungus, trauma, or more than one condition? Do I need a nail clipping or other test? Which treatment can reduce the material under the nail without damaging the nail bed? Would a procedure such as [Curettage And Cautery](/treatments/surgical-dermatology/curettage-and-cautery/) be appropriate, or is medical treatment preferable?