What should you know about brittle white nails?

Nails can become fragile after frequent wetting and drying, picking, biting, filing, or contact with harsh cleaning products. White marks may arise from minor injury to the nail as it grows. A nail fungus can cause whitening, thickening, crumbling, or separation from the nail bed. Nail psoriasis may create pits, ridges, discolouration, or lifting. One affected nail is different from several nails changing together, and the timing of the change helps a clinician narrow the possibilities.

The visible nail is made of keratin and grows gradually, so a cause may have started weeks before the change becomes obvious. Do not assume that white colour alone identifies an infection.

Keep nails short and smooth sharp edges with a fine file. Wear gloves for prolonged contact with water or detergents, dry hands carefully, and moisturise the nails and surrounding skin after washing. Avoid peeling polish, aggressive buffing, cuticle cutting, and nail hardeners that sting. Do not share nail tools, and keep tools clean and dry. Photograph the nails occasionally so you can notice whether changes are moving outward with growth or spreading to new nails.

If scaling between toes, itching, nail thickening, or crumbling accompanies the change, arrange an assessment for [Nail Fungus](/conditions/nail-fungus/). A clinician may examine or test nail material before recommending treatment; oral treatment is not suitable for everyone.

Arrange a dermatology review if the change persists despite gentle care, affects several nails, causes pain, or includes swelling, drainage, marked thickening, or nail lifting. Seek prompt medical attention for rapidly spreading redness, warmth, pus, severe pain, fever, or a dark streak that is new or widening. These signs need assessment rather than cosmetic cover-up. Persistent colour change can be discussed through [Discoloured Nails](/symptoms/nail-discoloration/) and may sometimes occur with [Nail Psoriasis](/conditions/nail-psoriasis/).

Ask what pattern they see, whether a nail sample is needed, which habits could be contributing, and whether skin findings elsewhere change the diagnosis. If infection is confirmed, ask why a particular treatment is chosen, how long improvement may take as the nail grows, and whether [Oral Antifungal Treatment](/treatments/medical-dermatology/oral-antifungal-therapy/) is appropriate for you.