Why does nail fungus cause brittle nails?

The fungus can live in and around the keratin that forms the nail. As the nail grows, affected layers may become rough, dry and less closely bonded. The edge can split, flake or peel, while pressure from shoes or repeated wetting and drying can worsen the breakage. Brittle Nails is a common presentation of Nail Fungus, but brittle nails can also follow injury, skin conditions or other nail changes. A clinician may examine the nail and, when needed, test a sample before choosing treatment.

Keep the nail trimmed straight across and file rough edges gently. Dry your feet and hands carefully after washing, change damp socks, and avoid sharing nail clippers or footwear. Do not scrape under the nail or cover a changing nail with cosmetic products for long periods, because this can hide progression. Treatment depends on how much of the nail is involved and whether nearby skin is affected; use only products recommended for your situation.

Arrange an assessment if the nail keeps crumbling, separates from the nail bed, becomes sore, or does not improve with careful nail hygiene. Seek prompt care for spreading redness, warmth, swelling, drainage or fever. People with diabetes, reduced circulation or a weakened immune system should seek advice early when a nail changes, because a small break can become harder to manage.

Could the brittle nail be fungal or another nail condition? Would a nail sample help confirm the cause? Which treatment fits the number of nails involved, and how should I protect the surrounding skin while the nail grows out?