Products
Fluconazole is commercially available in capsule form, as a powder for suspension, and as an infusion solution (Diflucan, generic). It has been approved in many countries since 1989.
Structure and properties
Fluconazole (C13H12F2N6O, Mr = 306.3 g/mol) is a fluorinated triazole derivative. It exists as a white, crystalline and hygroscopic powder that is sparingly soluble in water.
Effects
Fluconazole (ATC J02AC01) has antifungal (fungistatic) properties. The effects are due to inhibition of the enzyme lanosterol 14α-demethylase in fungal cells. This interrupts the conversion of lanosterol to ergosterol. This leads to accumulation of 14α-methylsterols and disruption of fungal cell membrane assembly.
Indications
Fluconazole is used for the prevention and treatment of fungal infections. These include:
- Candidamycosis: e.g., oral thrush, vaginal thrush, candidemia.
- Dermatophytoses: e.g. athlete’s foot.
- Cryptococcal meningitis, other cryptococcal infections.
Dosage
According to the drug label. The capsules are taken once a day, regardless of meals. The dosing interval depends on the indication. Some infections may be treated with a single dose (eg, vaginal thrush). Depending on the indication, daily or weekly dosing may also be necessary. Fluconazole has a long half-life of about 30 hours (range: 20-50 hours). The usual dose range is from 50 to 400 mg (adults). A suspension is available for children.
Contraindications
- Hypersensitivity
- Fluconazole must not be combined with drugs that are metabolized by CYP3A4 and simultaneously prolong the QT interval.
For complete precautions, see the drug label.
Interactions
Fluconazole has a high potential for interaction. It is a substrate of CYP3A4 and an inhibitor of CYP2C9, CYP2C19, and CYP3A4 and may cause corresponding drug-drug interactions.
Adverse effects
The most common possible adverse effects include abdominal pain, diarrhea, nausea, vomiting, elevated liver enzymes, skin rashes, and headache. Very rarely, serious adverse effects such as prolongation of the QT interval, liver damage, and severe skin damage may occur.