Thickening Skin Under Fingernails

The tissue beneath and around a nail can become rough or thick when it is repeatedly traumatised by biting, manicures, cleaning under the nail, or an injury. Inflammation may cause scaling, itch, tenderness, or altered nail growth. Atopic dermatitis can involve itchy, thickened skin around the hands and nails. Infection is another possibility, particularly when there is colour change, debris, lifting, or several nails affected. The nail itself can also become thicker, making it difficult to tell where the change begins. A clinician may need to inspect the nail, surrounding skin, and fingertip together.

Keep nails trimmed comfortably and clean them gently without scraping beneath the nail. Pause biting, picking, aggressive manicures, and products that sting. Wear gloves for wet work or contact with cleaning chemicals, and moisturise the hands and cuticles after washing. Do not share nail tools, and do not start a treatment intended for fungus without confirming the diagnosis. For background, see [Thickened Skin](/symptoms/skin-thickening/) and [Atopic Dermatitis](/conditions/atopic-dermatitis/).

Arrange a review when thickening lasts, affects one nail without an obvious injury, distorts nail growth, or is accompanied by pain or lifting. Seek prompt care for pus, marked swelling, severe throbbing, spreading redness, fever, or a dark streak or spot that changes. A nail-bed change after trauma also merits assessment if it does not gradually improve.

Ask whether the change is in the skin, nail plate, or nail bed, and whether testing is needed for infection. Ask how to protect the fingertip, which products to stop, and how long healthy nail growth should take before reassessment.