What should you know about mild nail fungus?

A change in one nail is not always a fungal infection, so a clinician can assess the pattern before recommending treatment.

The affected nail may become white, yellow, brown or less clear at an edge. Its surface can look dull, flaky or slightly uneven, and debris may collect beneath the free edge. Some nails gradually thicken or begin to lift from the nail bed.

Fungi can also affect the surrounding skin. Peeling, scaling or itching between the toes may occur with athlete's foot and can provide a route for infection to reach toenails. Keeping an eye on the skin as well as the nail is useful.

Keep nails trimmed straight across and gently file loose or rough material rather than tearing it. Dry feet carefully after washing, change damp socks, and avoid sharing clippers, nail files or footwear. Clean or replace personal nail tools if they have been used on the affected nail.

A clinician may consider a topical antifungal for a limited infection, while oral treatment may be considered when the infection is more extensive or difficult to clear. Treatment choices depend on the nail involved, other medicines and your health history.

Arrange a medical assessment when nail changes are spreading, causing pain, making shoes uncomfortable, or not improving with careful foot hygiene. Assessment is also sensible before using prescription treatment, because psoriasis, injury and other nail conditions can resemble fungal infection.

Seek prompt care for increasing redness, warmth, swelling, pus, fever, or a painful wound around the nail. People with diabetes, reduced circulation, reduced sensation in the feet or a weakened immune system should seek advice early for a new nail or skin problem.

Ask whether the appearance is likely to be fungus or whether a nail sample would help confirm the cause. You can also ask how to use a topical medicine, whether your regular medicines affect oral antifungal options, and how to prevent reinfection from shoes or athlete's foot.