Final answer:
Fungal infections in toenails cause symptoms such as thickened, discolored, and brittle nails, which may loosen or lift. The surrounding skin can become red, swollen, and painful, with an itching and burning sensation. In severe cases, pus and drainage can occur.
Step-by-step explanation:
Fungal infections of the toenails, also known as tinea unguium or onychomycosis, are commonly caused by dermatophytes or Candida species such as Candida albicans. The symptoms of a fungal nail infection can vary but typically include a combination of the following: the nail becoming thickened and discolored (often yellowish), becoming brittle and prone to breaking, a change in the shape of the nail, and the nail loosening or lifting from the nail bed. These infections can also lead to redness, swelling, and pain around the nail, as well as an itching and burning sensation on the adjacent skin. Additionally, in more severe cases, there can be formation of pus and drainage from under the nail.
It is important to note that toenails are more susceptible to fungal infections than fingernails due to conditions within shoes that provide a dark, warm, and moist environment conducive to fungal growth. Toenails also tend to receive less blood flow, making it more challenging for the body's immune system to combat infections. Treatments for toenail fungus often include over-the-counter antifungal creams, and in more persistent cases, prescription oral medications might be necessary.