Can nail fungus cause thickened nails?

Fungal changes can build up in and beneath the nail, making it look raised, uneven, or difficult to cut. The nail may also become yellowish, crumbly, or partly detached from the skin underneath. Pressure from footwear can then cause tenderness. Similar thickening may follow repeated trauma, ageing, or a skin disorder, so appearance alone cannot confirm the diagnosis.

Use properly cleaned nail tools and trim after bathing when the nail is softer, cutting across without digging into the sides. Choose footwear with enough room for the toes and keep feet dry. A clinician can assess the nail, check for a fungal cause when needed, and discuss topical or oral options suited to your health.

Arrange an appointment if the nail keeps thickening, becomes painful, or interferes with shoes. Seek prompt help for swelling, warmth, pus, spreading redness, or a nail that is lifting after an injury. Do not self-treat aggressively if you have diabetes, poor circulation, or reduced sensation in your feet.

Ask whether the thickness is caused by fungus, trauma, or a skin condition; whether a sample is useful; and how to trim the nail without injuring the surrounding skin.