Products
Antifungal products are commercially available as creams, ointments, powders, solutions, tablets, capsules, and injectables, among others.
Structure and properties
The antifungal agents are a structurally heterogeneous class of agents. However, several groups can be identified within the antifungals, such as the azole antifungals and the allylamines (see below).
Effects
Antifungals have antifungal, fungistatic, or fungicidal properties against dermatophytes, yeasts, and molds. Some are additionally antibacterial and antiparasitic, that is, effective against bacteria and parasites. Many antifungal agents (e.g., azole antifungals, allylamines) inhibit ergosterol synthesis. Ergosterol is an essential component of the fungal cell membrane that performs functions similar to those of cholesterol in animals. The drug targets are enzymes involved in biosynthesis. This leads to accumulation of toxic precursors and disruption of fungal cell membrane assembly. Echinocandins interfere with the biosynthesis of the polysaccharide 1,3-β-D-glucan, an important component of the fungal cell wall. The active ingredients also inhibit an enzyme. Several molecules of amphotericin B form pores in the cell membrane of fungi, leading to their dissolution. Ciclopirox blocks the uptake of vital substances into the fungal cell. Tavaborole selectively inhibits protein synthesis in fungi by inhibiting leucyl-tRNA synthetase, a correcting enzyme belonging to aminoacyl-tRNA synthetases.
Indications
For the treatment of fungal infections. Typical indications include:
- Athlete’s foot
- Nail fungus
- Skin fungus, diaper dermatitis, pityriasis versicolor, dandruff.
- -Infections such as an oral thrush and a vaginal fungus.
- Systemic fungal infections, e.g. invasive candidamycosis, aspergillosis.
Dosage
According to the professional information. The drugs are administered both topically and systemically (perorally, parenterally).
Active ingredients
A selection of active ingredients is shown below. For more information, see the drug groups. Azole antifungals:
- Clotrimazole (Canesten, Gyno-Canesten, generics).
- Econazole (Pevaryl)
- Fluconazole (Diflucan, generic)
- Itraconazole (Sporanox, generic).
- Ketoconazole (Nizoral, Terzolin, generics).
- Miconazole (Daktarin)
- Voriconazole (Vfend, generics)
Allylamine:
Polyene:
- Amphotericin B (Ampho-Moronal, Fungizone).
- Nystatin (Mycostatin)
- Pentamycin (no longer on the market in many countries).
Morpholine derivatives:
- Amorolfine (Loceryl, generic).
Hydroxypyridone derivatives:
- Ciclopirox (e.g., dafnegil, ciclopoli).
Echinocandins:
- Anidulafungin (Ecalta, generic).
- Caspofungin (Cancidas, generics)
- Micafungin (Mycamine)
Fatty acids:
- Undecylenic acid (Undex)
Colorants:
- Gentian violet (magistral formulations).
Acids:
- Acetic acid, vinegar
- Citric acid
Pyrimidines:
- Flucytosine (Ancotil).
Thiocarbamate:
- Tolnaftate (Undex)
Inorganic compounds:
- Selenium disulfide (ectoselenium)
Benzylamines:
- Butenafine (not commercially available in many countries).
Oxaborole:
- Tavaborole (not commercially available in many countries).
Benzofurans:
- Griseofulvin (not commercially available in many countries).
Contraindications
Full precautions can be found in the drug label.
Interactions
Several antifungal agents, particularly the azole antifungals, are inhibitors of CYP450 isozymes and may cause corresponding interactions. When CYP substrates are taken concomitantly, their plasma concentrations may increase and the risk for adverse effects increases.
Adverse effects
Possible adverse effects of antifungal agents include (selection, examples from groups):
