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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: fluconazole (flew KON a zole)
Brand name(s): DIFLUCAN
GENERIC: available FAMILY: Drugs for Fungal Infection
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Fluconazole has caused harm to developing fetuses in animal studies, including bone abnormalities of the skull. There have been reports of multiple congenital abnormalities in children born to mothers taking fluconazole. Because of the potential for serious adverse effects to the fetus, this drug should not be used by pregnant women.

The Food and Drug Administration (FDA) is informing the public that treatment with chronic, high doses (400-800 mg/day) of DIFLUCAN (fluconazole) during the first trimester of pregnancy may be associated with a rare and distinct set of birth defects in infants. This risk does not appear to be associated with a single, low dose of fluconazole (150 mg) to treat vaginal yeast infection (candidiasis). 

Breast-feeding Warning

Fluconazole is excreted in human milk. Because of the potential for adverse effects in nursing infants, you should not take this drug while nursing.

Safety Warnings For This Drug [top]

Liver toxicity

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. Patients who develop abnormal liver function tests during fluconazole therapy should be monitored for the development of more severe hepatic injury. Fluconazole should be discontinued if clinical signs and symptoms consistent with liver disease develop that may be attributable to the drug. (2)

Anaphylaxis 

In rare cases, anaphylaxis, a severe, potentially life-threatening allergic reaction, has been reported in patients taking fluconazole.

Skin toxicity

Serious skin reactions, known as exfoliative skin disorders, during treatment with fluconazole have been reported. Fatal outcomes have been reported in patients with serious underlying diseases. Patients with deep-seated fungal infections who develop rashes during treatment with fluconazole should be monitored closely and the drug discontinued if lesions progress. Fluconazole should be discontinued in patients treated for superficial fungal infection who develop a rash that may be attributed to fluconazole.

Facts About This Drug [top]

Fluconazole is used to treat severe fungal infections (such as meningitis) and infections of the mouth or esophagus (such as candida).[1],[2] Often these infections occur when another condition (such as cancer, organ transplant or HIV infection) reduces immunity to infections. The drug should not be used to treat trivial fungal skin infections.

Fluconazole is also approved by the Food and Drug Administration (FDA) to treat vaginal yeast infections (vaginal candidiasis) in a single dose of...

Fluconazole is used to treat severe fungal infections (such as meningitis) and infections of the mouth or esophagus (such as candida).[1],[2] Often these infections occur when another condition (such as cancer, organ transplant or HIV infection) reduces immunity to infections. The drug should not be used to treat trivial fungal skin infections.

Fluconazole is also approved by the Food and Drug Administration (FDA) to treat vaginal yeast infections (vaginal candidiasis) in a single dose of 150 milligrams (mg).[3]

Adverse effects

Some drugs in the azole family, including fluconazole, have been associated with the prolongation of the QT interval. QT prolongation is a change in the electrical activity of the heart that can lead to a fatal heart rhythm disturbance called torsades de pointes, resulting in sudden death. During postmarketing surveillance of fluconazole, there have been rare cases of QT prolongation and torsades de pointes. Most of these reports involved seriously ill patients with multiple confounding risk factors (such as structural heart disease, electrolyte abnormalities and concomitant medications) that may have been contributory.

Fluconazole should be administered with caution to patients with these potential pro-arrhythmic conditions. Also, other drugs known to cause QT interval prolongation, such as erythromycin, should not be administered to patients taking fluconazole.

Patients who develop a rash while being treated with fluconazole for deep-seated fungal infections should be monitored carefully, and the drug should be stopped if the rash progresses. The drug should be discontinued in patients who develop a rash while taking fluconazole for superficial fungal infections.

In 2020, BMJ published an article warning about a small increased risk of musculoskeletal (muscle and bone) malformations in children born to mothers who used fluconazole during the first trimester of pregnancy.

Regulatory actions surrounding fluconazole

2011: In August, the FDA issued a safety communication that long-term (chronic) high-dose (400-800 mg/day) use of fluconazole during the first trimester of pregnancy may be associated with a rare and distinct set of birth defects in infants. (See warning box under “Safety Warnings for This Drug” section, at top of this page.)[4]

2016: The FDA is evaluating data from a Danish study on the possible increased risk of miscarriage associated with the use of oral fluconazole.[5]

Before You Use This Drug [top]

Do not use if you have or have had:

  • allergy to azole antifungals
  • congestive heart failure

Tell your doctor if you have or have had:

  • pregnancy or are breast-feeding
  • lack of stomach acid
  • kidney or liver problems
  • alcohol abuse

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • If you plan to have any surgery, including dental, tell your doctor that you take this drug.
  • Check with your doctor if there is no improvement within a few days.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take this drug for the prescribed length of time. If you stop too soon, your symptoms could come back.
  • Take with or without food.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

amitriptyline, CELEBREX, celecoxib, cilostazol, COUMADIN, cyclosporine, DECADRON, DETROL, dexamethasone, DILANTIN, DURAQUIN, ELAVIL, glipizide, GLUCOTROL, HEXADROL, lovastatin, MEVACOR, mizolastine, NEORAL, phenytoin, PLETAL, PRIFTIN, PROGRAF, QUINAGLUTE DURA-TABS, QUINIDEX, quinidine, RETROVIR, RIFADIN, rifampin, rifapentine, RIMACTANE, SANDIMMUNE, simvastatin, tacrolimus, tolterodine, warfarin, zidovudine, ZOCOR.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • unusual bleeding or bruising
  • stomach pain
  • fever and chills
  • sore throat
  • skin rash
  • yellowing of eyes or skin
  • reddened, blistering, itching, or peeling skin or mucous membranes
  • dark or amber-colored urine
  • loss of appetite
  • pale stools
  • unusual tiredness or weakness

Call your doctor if these symptoms continue:

  • abdominal pain
  • dizziness
  • drowsiness
  • fatigue
  • headache
  • nausea or vomiting
  • diarrhea
  • constipation
  • loss of appetite
  • decreased sexual ability
  • menstrual irregularities
  • increased sensitivity of eyes to light
  • enlarged breasts in men

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • blood creatinine levels
  • blood urea nitrogen (BUN)
  • liver function tests
  • potassium levels

last reviewed April 30, 2021