Written on:

18 July, 2017

What Are Symptoms of Fungus Under the Toenail?

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Symptoms of fungus under the toenail can be barely noticeable or obvious at a glance. Toenail fungus can cause problems that require treatment. Appearance aside, toenail fungus can be painful. Nail hygiene becomes more difficult. Finding the right shoes can even become an issue. A fungus is an infection that especially thrives in the warm, moist environment of a sock and shoe. If left untreated, toenail fungus can worsen, affect walking and balance and result in separation of the nail from the toe. A podiatrist can diagnose symptoms of toenail fungus and recommend treatment

Changes in the Toenail

Mild toenail fungus symptoms include dull toenails that lack luster. Some yellowing might be present. The early beginnings of infection include a small white or yellow spot on the tip of the toenail. The nail may be dry and brittle. Eventually, the fungus will spread from the superficial area of the toenail into the nail bed.


Onychomycosis is a type of toenail fungus that affects the tissue underneath the toenail. The most common type of fungus that invades fingernails and toenails are dermatophytes. Symptoms of fungus under the toenail include darkening of the nail and a foul odor. As the fungus continues to invade, the nail begins to separate from the toe. The nail becomes thick and begins to crumble. Toenail fungus also leads to splitting and disfiguration of the nail. Pain occurs when shoes press against the nail bed. The pain associated with toenail fungus is caused by inflammation.

Fungus or Bacteria?

Symptoms of toenail fungus can vary. Only portion of the toenail bed might be affected, or the entire toenail might be involved. One or all of the toes might be affected. Inflammation can cause oozing from under the toenail. Symptoms of toenail fungus can mimic that of a yeast or bacterial infection. Diabetics with toenail bed infections could develop ulcers, making it important to differentiate between fungal toenail infection and bacterial or yeast infection, which each require different treatments.