Overview of Fungal Skin Infections

ByDenise M. Aaron, MD, Dartmouth Geisel School of Medicine
Reviewed/Revised Sept 2023
VIEW PROFESSIONAL VERSION

Fungi usually live in moist areas of the body where skin surfaces meet: between the toes, in the genital area, and under the breasts. Yeasts and molds are types of fungi.

Candida and Malassezia furfur are yeasts that cause common fungal infections.

Epidermophyton, Microsporum, and Trichophyton are dermatophytes that cause fungal infections. Dermatophytes are molds (a type of fungi).

Many of these fungi live only in the outermost layer of the skin (stratum corneum) and do not penetrate deeper.

People with obesity are more likely to develop these infections because they have excessive skinfolds, especially if the skin within a skinfold becomes irritated and broken down (intertrigo). People with diabetes tend to be more susceptible to fungal infections as well.

Strangely, fungal infections on one part of the body can cause rashes to appear on other parts of the body that are not infected. For example, a fungal infection on the foot may cause an itchy, bumpy rash on the fingers. These eruptions, called dermatophytid reactions, are allergic reactions to the fungus. They do not result from touching the infected area.

Diagnosis of Fungal Skin Infections

  • Skin scrapings or cultures

Doctors may suspect a fungal infection when they see a red, irritated, or scaly rash in one of the commonly affected areas.

They can usually confirm the diagnosis of a fungal skin infection by scraping off a small amount of skin and having it examined under a microscope or placed in a culture medium where the specific fungus can grow and be identified.

Treatment of Fungal Skin Infections

  • Antifungal medications

  • Measures to prevent moisture

Fungal infections are typically treated with antifungal medications, usually with ones that are applied directly to the affected area (called topical medications). Topical medications may include creams, gels, lotions, solutions, or shampoos.

Antifungal medications may also be taken by mouth.

In addition to medications, people may use measures to keep the affected areas dry, such as applying powders or wearing open-toed shoes.

Corticosteroids can help relieve inflammation and itching caused by some infections, but these should be used only when prescribed by a doctor.

Some Antifungal Medications Applied to the Skin (Topical Medications)

  1. Amorolfine (not available in the United States)

  2. Undecylenate (undecylenic acid, undecylenate salts, zincundecate)

quizzes_lightbulb_red
Test your KnowledgeTake a Quiz!
Download the free MSD Manual App iOS ANDROID
Download the free MSD Manual App iOS ANDROID
Download the free MSD Manual App iOS ANDROID