Fluconazole
An antifungal taken by mouth, most often as a single dose for vaginal thrush, and in longer courses for candidiasis elsewhere in the body.
- Class
- Triazole antifungal
- Sold as
- Sold as: Diflucan
- Prescription only
From the approved label
Fluconazole
- Approved uses
- Fluconazole tablets are indicated for the treatment of: Vaginal candidiasis (vaginal yeast infections due to Candida).
- Oropharyngeal and esophageal candidiasis.
- In open noncomparative studies of relatively small numbers of patients, fluconazole tablets were also effective for the treatment of Candida urinary tract infections, peritonitis, and systemic Candida infections including candidemia, disseminated candidiasis, and pneumonia.
- Cryptococcal meningitis.
- Forms and strengths
- Bottles of 30 NDC 65862-059-30 Bottles of 100 NDC 65862-059-01 Bottles of 500 NDC 65862-059-05 Fluconazole Tablets USP, 150 mg are pink mottled, biconvex, capsule shaped uncoated tablets with "C"...
- How it is taken
- Dosage and Administration in Adults: Single Dose Vaginal candidiasis: The recommended dosage of fluconazole tablets for vaginal candidiasis is 150 mg as a single oral dose.
- Multiple Dose SINCE ORAL ABSORPTION IS RAPID AND ALMOST COMPLETE, THE DAILY DOSE OF FLUCONAZOLE IS THE SAME FOR ORAL AND INTRAVENOUS ADMINISTRATION.
- In general, a loading dose of twice the daily dose is recommended on the first day of therapy to result in plasma concentrations close to steady-state by the second day of therapy.
- The daily dose of fluconazole tablets for the treatment of infections other than vaginal candidiasis should be based on the infecting organism and the patient's response to therapy.
- Must not be used when
- Fluconazole tablets are contraindicated in patients who have shown hypersensitivity to fluconazole or to any of its excipients.
- There is no information regarding cross-hypersensitivity between fluconazole and other azole antifungal agents.
- Caution should be used in prescribing fluconazole tablets to patients with hypersensitivity to other azoles.
- Coadministration of other drugs known to prolong the QT interval and which are metabolized via the enzyme CYP3A4 such as erythromycin, pimozide, and quinidine are contraindicated in patients receiving fluconazole.
- Interactions
- Drug Interaction Studies (See PRECAUTIONS, Drug Interactions) Oral contraceptives: Oral contraceptives were administered as a single dose both before and after the oral administration of fluconazole 50 mg once daily for 10 days in 10 healthy women.
- There was no significant difference in ethinyl estradiol or levonorgestrel AUC after the administration of 50 mg of fluconazole.
- The mean increase in ethinyl estradiol AUC was 6% (range: -47 to 108%) and levonorgestrel AUC increased 17% (range: -33 to 141%).
- In a second study, twenty-five normal females received daily doses of both 200 mg fluconazole tablets or placebo for two, ten-day periods.
- Warnings and precautions
- Hepatic injury: Fluconazole should be administered with caution to patients with liver dysfunction.
- Fluconazole has been associated with rare cases of serious hepatic toxicity, including fatalities primarily in patients with serious underlying medical conditions.
- In cases of fluconazole-associated hepatotoxicity, no obvious relationship to total daily dose, duration of therapy, sex, or age of the patient has been observed.
- Fluconazole hepatotoxicity has usually, but not always, been reversible on discontinuation of therapy.
- Common side effects
- Fluconazole is generally well tolerated. In some patients, particularly those with serious underlying diseases such as AIDS and cancer, changes in renal and hematological function test results and hepatic abnormalities have been observed during treatment with fluconazole and comparative agents, but the clinical significance and relationship to treatment is uncertain.
- Pregnancy
- Teratogenic Effects. Potential for Fetal Harm: Use in pregnancy should be avoided except in patients with severe or potentially life-threatening fungal infections in whom fluconazole may be used if the anticipated benefit outweighs the possible risk to the fetus. A few published case reports describe a pattern of distinct congenital anomalies in infants exposed in utero to high dose maternal fluconazole (400 to 800 mg/day) during most or all of the first trimester.
- How it acts
- Microbiology Mechanism of Action Fluconazole is a highly selective inhibitor of fungal cytochrome P450 dependent enzyme lanosterol 14-α-demethylase. This enzyme functions to convert lanosterol to ergosterol.
- Label holder:
- Aurobindo Pharma Limited
- Label version:
This section reports the approved product information. The wording is condensed from the regulator's own summary, and the full document is linked under Sources.
Written by us
How it works
Fluconazole blocks an enzyme the fungus needs to build its cell membrane, so the fungal cell stops growing. It acts on the fungus and not on the bacteria that cause other kinds of discharge, which is why the label lists candidiasis specifically rather than infection in general.
Original and generic
Off patent everywhere and inexpensive as a generic. Diflucan is the original brand and there is no clinical argument for paying more for it.
What it costs
A single tablet for vaginal candidiasis costs very little; the price of a course rises with the longer regimens the label describes for other forms of candidiasis.
How to get it legally
Legal status differs by country: in several European countries the single 150 mg dose is sold in a pharmacy without a prescription, while elsewhere it stays prescription only. Where a prescription is needed, an online consultation fits a recurrence someone recognises, and less well a first episode, because more than one condition produces the same symptoms.
Questions
- Is one tablet really the whole treatment?
- For vaginal candidiasis the label describes a single oral dose. Other forms of candidiasis in the same label are treated with longer courses, so the dose depends on what is being treated.
- Does it affect the contraceptive pill?
- The label reports interaction studies with oral contraceptives and gives the measured changes. That is a question to raise with the prescriber, since the answer depends on the dose and the pill in question.
- Why does the label warn about the liver?
- It records rare cases of serious liver toxicity and advises caution in people with liver dysfunction. It is a warning to disclose an existing liver condition, not a reason for a healthy person to avoid a single dose.
Sources
- Fluconazole: prescribing informationDailyMed, US National Library of Medicine. Label version 14 November 2024
- Drugs@FDA: ANDA077731US Food and Drug Administration
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