Fluconazole belongs to a group of medications known as antifungals. It is most commonly used to treat fungal infections of the mouth (thrush), esophagus (the tube that takes food from the throat to the stomach), lungs, urinary tract, and vagina (yeast infection). It works by preventing the fungi that are causing infection from reproducing and the infection from continuing. The fungi then die off, causing the infection to clear.

It is also used to treat cryptococcal meningitis and prevent the recurrence of cryptococcal meningitis for people with acquired immunodeficiency syndrome (AIDS), and to decrease the risk of candidiasis infection for people undergoing bone marrow transplants who are treated with chemotherapy or radiation therapy.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

To treat thrush (yeast infection of the mouth and throat), the recommended adult dose is 100 mg taken by mouth once daily for at least 2 weeks.

To treat esophageal candidiasis (yeast infection of the tube leading to the stomach), the recommended adult dose ranges from 100 mg to 200 mg taken daily for at least 3 weeks. Fluconazole must be taken for at least 2 weeks after the symptoms of the infection resolve to prevent the infection from returning.

To treat yeast infection that has spread throughout the body (disseminated yeast infection), the recommended adult dose of fluconazole is 200 mg to 400 mg once daily, for at least 4 weeks. Again, this medication must be taken for at least 2 weeks after the symptoms of the infection resolve to prevent the infection from returning.

To treat cryptococcal meningitis, the recommended dose of fluconazole is 200 mg to 400 mg once daily. Fluconazole should be taken for at least 10 weeks when treating this condition. To prevent cryptococcal meningitis, 200 mg taken once daily is recommended.

Children's doses are based on the child's body weight and will be calculated by the prescriber. A child's dose should not be more than 12 mg per kilogram of body weight.

The recommended adult dose to prevent candidiasis associated with bone marrow transplant is 400 mg taken once daily.

Doses greater than 600 mg daily are not recommended for adults or children.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is very important to take this medication on a regular schedule as prescribed by the doctor. Continue to take the full course of this medication even if you start to feel better. If you miss a dose of this medication, take it as soon as you remember it. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature and keep it out of the reach of children. The reconstituted liquid is stable for two weeks at room temperature.

Do not take this medication if you:

• are allergic to fluconazole or to any of the ingredients of the medication
• are taking cisapride, erythromycin, pimozide, or quinidine

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• diarrhea
• headache
• nausea
• stomach pain
• vomiting

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• skin rash or itching
• symptoms of drug hypersensitivity
• symptoms of irregular heartbeat (e.g., chest pain, dizziness, rapid, pounding heartbeat, shortness of breath)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a severe allergic reaction (hives; difficulty breathing; swelling of the face, tongue, or throat)
• symptoms of a severe skin rash (such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Adrenal gland problems: Adrenal glands produce chemical messengers that are responsible for the normal function of the body’s organs, including how your body responds to injury or stress. On rare occasions, fluconazole may cause your adrenal gland to function improperly. This frequently returns to normal after stopping the medication. Your doctor may monitor your adrenal gland condition especially if you have experienced stress such as surgery, injury, or severe infection.

Allergies: Be cautious in taking fluconazole if you are allergic to other "azoles" such as ketoconazole or itraconazole. If you develop symptoms of an allergic reaction, such as skin rash; hives; difficulty breathing; or swelling of the face, tongue, or throat; seek immediate medical attention.

In rare cases, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS syndrome) may occur. This reaction involves symptoms including fever, swollen glands, yellowing of the skin or eyes, flu-like symptoms with skin rash or blistering, or other organ involvement. These reactions are medical emergencies. Get immediate medical attention if you have symptoms of a severe allergic reaction. If you experience any unusual symptoms, contact your doctor.

Driving and operating heavy machinery: Fluconazole may occasionally cause dizziness. Do not drive or operate machinery until you know how this medication affects you.

Kidney function: Decreased kidney function or kidney disease can cause this medication to build up in the body, causing side effects. People with kidney disease or reduced kidney function should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Lactose or sucrose intolerance: The powder for oral suspension contains lactose and sucrose.  If you have hereditary problems with either lactose or sucrose you should not use this form of fluconazole.

Liver damage: In rare cases, this medication may cause liver damage for people with serious medical conditions. Your doctor may monitor you with regular blood tests to check for side effects while you are taking fluconazole. If you notice signs of liver damage such as abdominal pain, yellowing of the skin or eyes, dark or amber urine, or pale stools, contact your doctor right away.

QT prolongation: In rare cases, this medication can affect the electrical activity of the heart and cause a condition known as QT prolongation. Your doctor will monitor your heart rhythm regularly while you are taking this medication with a test called an electrocardiogram (ECG). You should not take this medication if your ECG already shows that you have QT prolongation or if you are taking a medication that can cause QT prolongation.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately. People who take fluconazole and who may become pregnant should consider using adequate birth control. Birth control should be continued for at least 1 week after taking the last dose of fluconazole.

Breast-feeding: This medication passes into breast milk. If you are breast-feeding and taking fluconazole, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: This medication has been shown to be safe and effective for children over 6 months of age. Although the safety and effectiveness of this medication have not been determined for newborns less than 6 months of age, a small number of babies have been safely treated with fluconazole.

There may be an interaction between fluconazole and any of the following:

• alitretinoin
• alpha-blockers (e.g., alfuzosin, silodosin, tamsulosin)
• amiodarone
• anti-psychotics (e.g., aripiprazole, cariprazine, chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
• apixaban
• aprepitant
• atogepant
• avacopan
• benzodiazepines (e.g., alprazolam, diazepam, triazolam)
• birth control pills
• bosentan
• bromocriptine
• buprenorphine
• buspirone
• calcitriol
• calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
• cancer medications (e.g., busulfan, capecitabine, docetaxel, ifosfamide, irinotecan, temsirolimus, vinblastine, vincristine)
• cannabis
• carvedilol
• CF transmembrane regulators (e.g., elexacaftor, ivacaftor, lumacaftor, tezacaftor)
• chloroquine
• citalopram
• clindamycin
• clopidogrel
• colchicine
• cyclosporine
• dabigatran
• daridorexant
• darifenacin
• disopyramide
• domperidone
• doxepin
• dronedarone
• eletriptan
• eliglustat
• eplerenone
• ergot alkaloids (e.g., ergotamine, dihydroergotamine)
• escitalopram
• eszopiclone
• estrogens (e.g., conjugated estrogen, estradiol, ethinyl estradiol)
• everolimus
• finerenone
• flecainide
• flibanserin
• general anesthetics (medications to put you to sleep for surgery)
• guanfacine
• HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., etravirine, nevirapine)
• HIV protease inhibitors (e.g., atazanavir, lopinavir, ritonavir, tipranavir)
• inhaled corticosteroids (e.g., budesonide, ciclesonide, fluticasone)
• inotuzumab
• ivabradine
• lemborexant
• lidocaine
• lomitapide
• losartan
• macitentan
• macrolide antibiotics (e.g., azithromycin, clarithromycin, erythromycin)
• maraviroc
• mavacamten
• methadone
• mifepristone
• moclobemide
• naloxegol
• narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone, tramadol)
• non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, ketorolac, naproxen)
• ondansetron
• oral corticosteroids (e.g., dexamethasone, methylprednisolone)
• ospemifene
• other "azole" antifungals (e.g., itraconazole, voriconazole)
• phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)
• pimecrolimus
• pimozide
• praziquantel
• procainamide
• progestins (e.g., dienogest, levonorgestrel, medroxyprogesterone, norethindrone)
• proguanil
• propafenone
• protein kinase inhibitors (e.g., crizotinib, dasatinib, imatinib, nilotinib, tofacitinib, vandetanib)
• proton pump inhibitors (e.g., dexlansoprazole, lansoprazole, omeprazole)
• quinine
• quinolone antibiotics (e.g., levofloxacin, moxifloxacin)
• ranolazine
• rifabutin
• rifampin
• rivaroxaban
• roflumilast
• rupatadine
• saccharomyces boulardii
• salmeterol
• saxagliptin
• seizure medications (e.g., carbamazepine, clobazam, phenytoin)
• siponimod
• sirolimus
• solifenacin
• sotalol
• "statin" cholesterol medications (e.g., atorvastatin, lovastatin, simvastatin)
• sulfonylureas (e.g., glyburide, gliclazide)
• tacrolimus
• terbutaline
• theophyllines (e.g., aminophylline, theophylline)
• ticagrelor
• tolterodine
• tolvaptan
• trazodone
• tretinoin
• tricyclic antidepressants (e.g., amitriptyline, desipramine, imipramine)
• vilazodone
• warfarin
• zopiclone

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, decongestants, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.