Fungi can be found throughout the world in all kinds of environments. Most fungi don’t cause disease in people. However, some species can infect humans and cause illness.
Antifungal drugs are medications that are used to treat fungal infections. While most fungal infections affect areas such as the skin and nails, some can lead to more serious and potentially life threatening conditions like meningitis or pneumonia.
There are several types of antifungal drugs available to fight fungal infections.
Generally speaking, antifungal drugs can work in two ways: by directly killing fungal cells or by preventing fungal cells from growing and thriving. But how do they do this?
Antifungal drugs target structures or functions that are necessary in fungal cells but not in human cells, so they can fight a fungal infection without damaging your body’s cells.
Two structures that are commonly targeted are the fungal cell membrane and the fungal cell wall. Both of these structures surround and protect the fungal cell. When either one becomes compromised, the fungal cell can burst open and die.
Antifungal drugs are very diverse. They can be given orally, as a topical treatment, or via IV. How an antifungal drug is given depends on factors like the specific drug, the type of infection you have, and the severity of your infection.
Antifungal drugs are classified by their chemical structure as well how they work. Below, we’ll discuss the different types of antifungal drugs and give some examples of the types of infections they treat.
Azoles are some of the most commonly used antifungals. They interfere with an enzyme that’s important for creating the fungal cell membrane. Because of this, the cell membrane becomes unstable and can leak, eventually leading to cell death.
There are two subgroups of azole antifungals: imidazoles and triazoles.
Examples of imidazole antifungals and the conditions they treat are:
- Ketoconazole: infections of the skin and hair, Candida infections of the skin and mucous membranes, blastomycosis, histoplasmosis
- Clotrimazole: skin and mucous membrane infections
- Miconazole: skin and mucous membrane infections
Some examples of triazoles and the conditions they treat are:
- Fluconazole: Candida infections, including mucosal, systemic, and invasive infections; cryptococcosis
- Itraconazole: aspergillosis, blastomycosis, histoplasmosis, mucosal Candida infections, coccidioidomycosis (off-label), and onychomycosis
- Posaconazole: aspergillosis (off-label for treatment), mucosal and invasive Candida infections
- Voriconazole: aspergillosis, mucosal or invasive Candida infections, infections with Fusarium species
- Isavuconazole: aspergillosis and mucormycosis
Polyenes kill fungal cells by making the fungal cell wall more porous, which makes the fungal cell prone to bursting.
Some examples of polyene antifungals are:
- Amphotericin B: various formulations are available to treat aspergillosis, blastomycosis, cryptococcosis, histoplasmosis (off-label), mucosal or invasive Candida infections, and coccidioidomycosis
- Nystatin: Candida infections of the skin and mouth
Like the azole antifungals, allylamines interfere with an enzyme that’s involved in the creation of the fungal cell membrane. One example of an allylamine is terbinafine, which is often used to treat fungal infections of the skin.
Echinocandins are a newer type of antifungal drug. They inhibit an enzyme that’s involved in the making of the fungal cell wall.
Some examples of echinocandins are:
- Anidulafungin: mucosal and invasive Candida infections
- Caspofungin: mucosal and invasive Candida infections, aspergillosis
- Micafungin: mucosal and invasive Candida infections
There are also some other types of antifungal medications. These have mechanisms different from the types we’ve discussed above.
Flucytosine is an antifungal that prevents the fungal cell from making nucleic acids and proteins. Because of this, the cell can no longer grow and thrive. Flucytosine can be used to treat systemic infections with Candida or Cryptococcus species.
Griseofulvin works to prevent the fungal cell from dividing to produce more cells. It can be used to treat infections of the skin, hair, and nails.
There are many types of fungal infection. You can get a fungal infection by coming into contact with a fungus or fungal spores that are present in the environment.
Some of the most common fungal infections are those of the skin, nails, and mucous membranes. Examples include:
- Ringworm (also known as tinea): a fungal infection of the skin that can occur on your scalp, on your feet (athlete’s foot), in your groin area (jock itch), and on other areas of your body
- Nail fungus: an infection that typically affects your toenails but can also affect your fingernails
- Vaginal yeast infection: an infection that occurs due to overgrowth of Candida yeast in and around the vagina
- Oral thrush: a condition in which Candida yeast overgrows in your mouth
More serious fungal infections
Examples of fungal species that can cause more serious infections include:
Who’s at risk for a fungal infection?
While fungal infections can happen to anyone, they’re more common in people with weakened immune systems. People who may have weakened immune systems include those who are:
The symptoms of some of the common types of fungal infections can include:
- Ringworm of the body: a scaly, potentially itchy ring-shaped rash on your torso, arms, or legs
- Ringworm of the scalp: localized scaly patches, pustules, or plaques on your scalp that are itchy and may be tender and result in hair loss
- Athlete’s foot: scaly skin on the bottom of your feet
- Jock itch: an itchy, red rash that appears in your groin area and on your inner thighs
- Nail fungus: nails that become discolored, brittle, and deformed
- Vaginal yeast infection: itching, redness, and swelling in the vaginal area — thick white vaginal discharge and a burning sensation when urinating may also occur
- Oral thrush: development of white lesions in your mouth that may also be red and painful
Symptoms of more serious fungal infections
The symptoms of some of the more serious fungal infections can vary depending on which species of fungi is causing the infection and the area of your body that’s affected.
They can include things like:
Make an appointment with your doctor if:
- over-the-counter (OTC) antifungals haven’t worked to relieve the symptoms of infections like ringworm, nail fungus, or a vaginal yeast infection
- unexplained white lesions develop in your mouth
- you have a fever, flu-like symptoms, or a worsening rash and/or you suspect a fungal infection
There are some symptoms for which you should always seek prompt medical attention
Antifungal drugs are used to treat fungal infections. They target processes and structures unique to fungi in order to kill fungal cells or prevent them from growing.
There are many types of antifungal drugs, and they can be given in several different ways. The type of drug used and the way it’s administered can depend on the drug and the type and severity of the infection.
While many types of fungal infections are easily treated, some can be serious. See your doctor if a fungal infection doesn’t go away with OTC treatment or if you suspect you have a more serious fungal infection.