Fluconazole

Pronunciation: floo-KOH-nah-zohl.

Generic name
fluconazole
Drug class
Triazole antifungal
Form
Capsule/tablet (50 mg, 100 mg, 150 mg, 200 mg), oral suspension, and solution for infusion
Route
Oral (capsule/tablet/oral suspension) or intravenous infusion
Legal status
Prescription-only for most strengths and uses; a single 150 mg dose for vaginal thrush is sold over-the-counter from pharmacies in some countries (confirmed for New Zealand and, under separate retail brand names, the United Kingdom).

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: Diflucan (4), Dizole / Femazole One / Flufeme / Canesoral (4) (5) · Full directory

What fluconazole is and how it works

Fluconazole is an antifungal medicine that works by blocking an enzyme fungi need to build their cell membranes. It treats a range of fungal (mainly Candida yeast) infections, from vaginal thrush treated with a single dose, to serious infections such as cryptococcal meningitis that need weeks of higher-dose treatment. (1) (2)

For the common single-dose vaginal thrush use, fluconazole is generally very well tolerated. For higher doses or longer courses, it has real, serious interactions with several other medicines and a small risk of liver problems and heart-rhythm changes, so it is important to tell your prescriber or pharmacist about every other medicine you take before starting it.

Mechanism of action: how fluconazole works

Fluconazole is a triazole antifungal that selectively inhibits fungal cytochrome P450-dependent 14-alpha-demethylase, blocking conversion of lanosterol to ergosterol, an essential component of the fungal cell membrane. It is also a moderate inhibitor of human CYP2C9 and CYP3A4 and a strong inhibitor of CYP2C19, the basis for its numerous, clinically significant drug interactions. (1) (2)

What fluconazole is used for

Vaginal thrush (vaginal candidiasis)

A single 150 mg dose is a standard treatment for vaginal yeast infections; recurrent vaginal thrush (4 or more episodes a year) may be treated with a longer maintenance course under a prescriber's guidance. (1) (2) (3)

Oral and oesophageal thrush

Used to treat thrush of the mouth/throat (oropharyngeal) and gullet (oesophageal), typically starting with a higher first-day dose followed by a lower daily dose. (1) (2)

Skin and nail fungal infections

Used for certain skin fungal infections (such as athlete's foot, ringworm of the body/groin, and pityriasis versicolor) and some nail fungal infections, usually as a weekly or daily dose over several weeks. (2) (3)

Cryptococcal meningitis and other serious/invasive fungal infections

Used, usually at higher doses for a period of weeks, to treat serious infections including cryptococcal meningitis and invasive candidiasis, and for prevention of fungal infection in people with a weakened immune system (such as after bone marrow transplant or with prolonged low white blood cell counts). (1) (2)

Before taking fluconazole

Do not take / not appropriate for

  • Do not take fluconazole if you have a known allergy to it or to other azole antifungal medicines. (all countries) (1) (2)
  • Do not take fluconazole together with quinidine, pimozide, cisapride, astemizole, or erythromycin -- these combinations are contraindicated because of a serious risk of dangerous heart rhythm changes. (all countries) (1) (2)
  • Do not take terfenadine together with fluconazole at repeated (multiple) fluconazole doses of 400 mg per day or higher. (all countries) (1) (2)

Tell your clinician about

  • All other medicines you take -- fluconazole has real, sometimes significant interactions with many common medicines, including warfarin, some diabetes tablets, phenytoin, ciclosporin, tacrolimus, and midazolam.
  • Any personal or family history of an irregular heart rhythm, or low blood potassium.
  • Any history of liver problems.
  • Whether you are pregnant, planning pregnancy, or breastfeeding.
  • Whether you have had 4 or more episodes of vaginal thrush in the past year, since this may need a different, longer treatment course.
(1) (2)

How to take fluconazole

  • Take fluconazole exactly as directed for your specific infection -- the dose, strength, and length of treatment vary widely depending on what is being treated.
  • For the standard single-dose vaginal thrush treatment, only one capsule is needed; for other uses, complete the full course even if you feel better sooner.
  • If your kidneys do not work normally, your prescriber may adjust your dose.
(1) (2)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5)

Missed dose

For a single-dose treatment, this does not apply. For a multi-dose course, if you miss a dose, take it as soon as you remember unless it is nearly time for your next dose -- do not take an extra dose. Contact your pharmacist or prescriber if you are unsure.

Overdose

Seek urgent medical attention if you think you have taken too much fluconazole, particularly if you develop an irregular heartbeat, severe dizziness, or fainting. Reported overdose symptoms have included hallucinations and paranoid behaviour; supportive care and, if needed, haemodialysis can help remove the drug. (2)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Headache.

What to notice: Headache.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (2)

Nausea, abdominal pain, diarrhoea, or vomiting.

What to notice: Nausea, abdominal pain, diarrhoea, or vomiting.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (2)

Skin rash.

What to notice: Skin rash.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (2)

Mildly raised liver enzymes on blood tests.

What to notice: Mildly raised liver enzymes on blood tests.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (2)

Serious warnings

Signs of serious liver problems — high caution

Symptoms: Unusual tiredness, loss of appetite, persistent nausea or vomiting, or yellowing of the skin or eyes (jaundice).

Action: Contact your clinician promptly -- rare but serious, sometimes fatal, liver injury has been reported, mainly in people with serious underlying illness. (1) (2)

Signs of a dangerous heart rhythm change — high caution

Symptoms: A fast, irregular, or pounding heartbeat, severe dizziness, or fainting.

Action: Seek urgent medical attention. Fluconazole can prolong the QT interval, which rarely can lead to a dangerous heart rhythm (torsade de pointes), particularly if you have low blood potassium, a heart rhythm condition, or advanced heart failure, or take other QT-affecting medicines. (1) (2)

Signs of a severe skin reaction — emergency

Symptoms: Widespread blistering or peeling skin, painful rash, or sores in the mouth, eyes, or genitals.

Action: Seek emergency medical help immediately and ask the prescriber about stopping it -- rare, serious skin reactions (including Stevens-Johnson syndrome and toxic epidermal necrolysis) have been reported. (1) (2)

Signs of a serious allergic reaction — emergency

Symptoms: Swelling of the face, lips, tongue, or throat; difficulty breathing; widespread hives.

Action: Seek emergency medical help immediately. (1)

Interactions

  • Warfarin and other coumarin-type anticoagulants: fluconazole can prolong prothrombin time (increase bleeding-test results) up to 2-fold -- closer monitoring is needed. (1) (2)
  • Oral diabetes medicines (sulfonylureas): fluconazole can cause clinically significant low blood sugar; one fatality has been reported. (1)
  • Phenytoin, ciclosporin, and tacrolimus: fluconazole significantly raises blood levels of these medicines, requiring dose adjustment and monitoring under specialist care. (1) (2)
  • Midazolam and other benzodiazepines taken by mouth: fluconazole markedly increases their levels and effects. (2)
  • Amiodarone and other QT-prolonging medicines: combining with fluconazole may increase the risk of a dangerous heart rhythm change. (1)
  • Voriconazole and abrocitinib: avoid combining with fluconazole. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Standard-dose, short-term fluconazole (including the single 150 mg thrush dose) should not be used in pregnancy unless clearly necessary, because observational studies suggest an increased risk of miscarriage in the first/second trimester; high-dose, prolonged use has been linked to a pattern of birth defects and is avoided except for life-threatening infections. (1) (2) (3) (4) (5)

Breastfeeding

Fluconazole passes into breast milk at levels similar to blood. Breastfeeding can generally continue after a single 150 mg dose, but is not recommended after repeated or high-dose use -- discuss with your clinician. (1) (2) (3) (4) (5)

Children

Used in children (including infants) for certain fungal infections, with weight-based dosing set by a paediatric specialist. (1) (2) (3) (4) (5)

Elderly

No specific dose adjustment based on age alone, but kidney function should be checked, since dose depends on kidney function. (1) (2) (3) (4) (5)

Hepatic_impairment

Use with caution; report any symptoms of liver problems immediately. (1) (2) (3) (4) (5)

Renal_impairment

Dose is adjusted (typically halved) based on kidney function (creatinine clearance) after any loading dose. (1) (2) (3) (4) (5)

Source_ids

US-FDA-DIFLUCAN-LABEL-2026,UK-EMC-DIFLUCAN-2026 (1) (2) (3) (4) (5)

Monitoring

Before starting

  • Review of all other medicines for interactions (especially warfarin, sulfonylureas, phenytoin, ciclosporin, tacrolimus, midazolam, and other QT-prolonging drugs)
  • Kidney function, if a longer course is planned
  • Baseline liver function, if a longer course or higher dose is planned

During treatment

  • Liver function tests if treatment is prolonged or symptoms of liver problems develop.
  • Blood potassium and heart rhythm monitoring in higher-risk patients on longer or higher-dose courses.
(1) (2)

Storage

Store at room temperature, protected from moisture, out of reach of children, following the specific product's packaging instructions.

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information and UK SmPC; verify against the current full label before prescribing.

United States / United Kingdom / European Union / Canada / Australia / New Zealand

Indication: Vaginal candidiasis

Dose summary: 150 mg single oral dose; recurrent disease 150 mg every third day x3 then 150 mg weekly for up to 6 months.

Renal context: No adjustment needed for single-dose use; maintenance dosing in renal impairment follows the general creatinine-clearance-based adjustment. (1) (2)

United States / United Kingdom / European Union / Canada / Australia / New Zealand

Indication: Cryptococcal meningitis / invasive candidiasis

Dose summary: 400 mg loading dose day 1, then 200-400 mg once daily for a minimum of 6-8 weeks (cryptococcal meningitis), individualised by specialist.

Renal context: After loading dose, halve the maintenance dose if creatinine clearance is 50 mL/min or less. (1) (2)

Mechanism of action

Hepatic guidance

Rare, sometimes fatal, hepatotoxicity has been reported, primarily in patients with serious underlying illness; monitor for signs of liver injury, particularly with prolonged or high-dose therapy.

Overdose note

Supportive care; haemodialysis can help remove fluconazole from the blood and may be useful in overdose or in patients with significant renal impairment. (1) (2)

Frequently asked questions

Is fluconazole available in the US, UK, Europe, Canada, Australia, and New Zealand?

Yes. It is marketed in all of these regions, mainly as Diflucan (Pfizer) with extensive generic availability. Confirmation is strongest for the US and UK (directly verified full prescribing information); Canada, Australia, and general EU-wide availability are confirmed via brand-name compilation sources rather than a directly fetched national regulator document this pass. (1) (2) (4) (3)

Can I buy fluconazole over the counter for thrush?

In New Zealand, a single 150 mg capsule for vaginal thrush can be bought over the counter from a pharmacy, while other strengths and uses need a prescription. A similarly licensed single-dose pharmacy product exists in the UK under separate retail brand names. Rules vary by country -- ask your local pharmacist. (3) (4)

Does fluconazole have a boxed warning?

No. Directly checking the current FDA prescribing information confirms fluconazole does not carry a formal boxed warning. It does carry serious Warnings and Precautions for rare liver injury, heart-rhythm (QT) prolongation, and rare adrenal suppression. (1)

Why does fluconazole interact with so many other medicines?

Fluconazole blocks several liver enzymes (CYP2C9, CYP3A4, and especially CYP2C19) that many other medicines rely on to be broken down, which can raise the levels of those other medicines -- this is why it's important to tell your prescriber and pharmacist about everything else you take. (1) (2)

What is the mechanism of action of fluconazole?

Fluconazole is a triazole antifungal that selectively inhibits fungal cytochrome P450-dependent 14-alpha-demethylase, blocking conversion of lanosterol to ergosterol, an essential component of the fungal cell membrane. It is also a moderate inhibitor of human CYP2C9 and CYP3A4 and a strong inhibitor of CYP2C19, the basis for its numerous, clinically significant drug interactions. (1) (2)

What is the generic name of Fluconazole?

The generic name is fluconazole. (1) (2)

What class of drug is fluconazole?

Fluconazole is classed as: Triazole antifungal. (1) (2)

References

  1. DIFLUCAN (fluconazole) -- FDA prescribing informationU.S. Food and Drug Administration prescribing information (mirrored in full by drugs.com's FDA-label reproduction; the underlying document is Pfizer's FDA-approved DIFLUCAN/fluconazole label) · United States · accessed 2026-07-30 · source 1
  2. Diflucan 150 mg hard capsules -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- Pfizer Limited · United Kingdom · accessed 2026-07-30 · source 2
  3. Fluconazole -- consumer medicine informationHealthify (New Zealand government-funded consumer health information service, referencing Medsafe datasheets/CMI) · New Zealand · accessed 2026-07-30 · source 3
  4. Fluconazole -- international brand namesDrugs.com International Drug Names database (a real, maintained secondary compilation of international brand names; NOT a primary regulator source -- used only to corroborate brand-name presence, not clinical claims) · Canada, Australia, New Zealand, United Kingdom, European Union (general) · accessed 2026-07-30 · source 4
  5. Fluconazole -- regulatory scheduling contextGeneral encyclopaedia entry (tertiary source, used only for general scheduling/context corroboration, never as evidence of a specific clinical claim) · General/multi-country · accessed 2026-07-30 · source 5

Brand names by country

Single-ingredient fluconazole names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Diflucan1400 mg/35mL · roerig

United Kingdom

  • Diflucan (2)MHRA licensed emc smpc confirmed · 50 mg, 150 mg, 200 mg, oral suspension · Pfizer Limited
  • Fluconazole (generic, e.g. Aurobindo/Milpharm) (2)MHRA licensed generic confirmed · 50 mg, 150 mg, 200 mg, injection · Multiple generic manufacturers
  • Boots Thrush 150 mg (single-dose OTC product for vaginal thrush) (4)separately licensed pharmacy medicine confirmed · 150 mg · The Boots Company

Canada

  • DIFLUCAN
  • DIFLUCAN INJ
  • DIFLUCAN ONE
  • DIFLUCAN PWS
  • FLUCONAZOLE OMEGA
  • CANESORAL
  • CO FLUCONAZOLE-150
  • MONICURE
  • FLUCONAZOLE INJECTION SDZ

Australia

  • Diflucan (4)marketed secondary compilation confirmed · 150 mg, and others · Pfizer
  • Dizole / Femazole One / Flufeme / Canesoral (4) (5)marketed secondary compilation confirmed · 150 mg, and others · Alphapharm / Arrow Pharmaceuticals / Sandoz / Bayer Consumer Care

New Zealand

  • Diflucan (3)Medsafe approved confirmed · 50 mg, 150 mg, 200 mg · Pfizer
  • Canesoral / Flonazol / Mylan Fluconazole / Flucastle One (3) (4)Medsafe approved confirmed · 150 mg, and others · Bayer / Mylan / Teva
View brands in additional countries.

European Union

Diflucan (4), Fluconazole (generic, e.g. Sandoz, Hexal, Krka) (4)

This page provides general reference information about fluconazole and is not a substitute for advice from your prescriber or pharmacist. All dosing and treatment decisions should be made with a qualified healthcare professional, especially if you take any other medicines.

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