Fluconazole: What It’s For, How to Use & Side Effects

Updated in December 2023

Fluconazole is an antifungal medication that inhibits the growth of fungus. It is especially efficient against Candida species, which can cause fungal infections on the skin, nails, groin, mouth, throat or genital organs.

Fluconazole is commonly prescribed for the treatment of oral thrush, genital yeast infections or skin mycosis. 

This medication can be accessed at pharmacies in tablet, liquid or IV solution forms with a prescription. It is usually found in strengths of 50 mg, 100 mg, 150 mg, and 200 mg. It should be used as prescribed by a health care provider. 

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What It’s For

Fluconazole is indicated for the treatment of fungal infections cause by Candida species, like:

  • Mild and recurrent vaginal yeast infections 
  • Male yeast infections that affect the head of the penis for example 
  • Athlete’s foot 
  • Jock itch, or mycosis affecting the groin
  • Onychomycosis, or fungal infection of finger or toe nails
  • Skim mycosis

This medication can also be taken prophylactically to prevent or reduce vaginal yeast infection flare-ups. 

It can also be prescribed to prevent fungal infections in people with weakened immune systems, like in people receiving cancer treatment, following a bone marrow transplant, or those with a history of HIV. 

How to Use It

Fluconazole use will vary depend on the underlying illness and form it is taken in. Some examples include: 

1. Fluconazole tablets

Fluconazole tablets can be accessed with a prescription or over the counter. They should be swallowed with a sip of water, and can be taken before or after a meal. Dosing should be followed as prescribed by the doctor. 

Fluconazole dosing will vary depending on what it is prescribed for. For example:

  • Vaginal or male yeast infections: One single dose of fluconazole 150 mg 
  • Recurrent vaginal yeast infections: One single of fluconazole 150 mg, repeated once per month for 4 to 12 months.
  • Athlete’s foot, jock stitch or skin mycosis: One single of fluconazole 150 mg, taken once per week for 2 to 4 weeks. In some cases, treatment of athlete’s foot can last for up to 6 weeks. 
  • Onychomycosis: One single dose of fluconazole 150 mg until the affected nail has grown out and is replaced with a healthy nail. This can take 3 to 6 months in fingernails and 6 to 12 months for toenails. 

Fluconazole should not be used by children, adolescents under 18 or older adults over 60, unless prescribed by the doctor. 

2. IV fluconazole

IV fluconazole should be administered intravenously by a doctor, nurse or health care professional. Dosing prescribed by the doctor will depend on the severity of the infection and type of fungus causing it. 

3. Fluconazole powders

There are different types of fluconazole powders that are taken orally or applied externally. Oral suspensions are a powder-form of the medication that can be pre-mixed at the pharmacy, or provided as a powder in a package to be mixed at home in water or other beverages. Once mixed, you drink it as directed by your doctor. 

Fluconazole powders that are applied externally, however, as usually applied directly to areas affected by yeast. For example, there are powders that are used to treat athlete’s foot or fungal toe nails available for purchase over-the-counter.

It is important to note that suspension powders are solely used for oral use and external powders should not be used or taken in other ways.

Possible side effects

The most common side effects that can occur with fluconazole treatment are nausea, diarrhea, stomach ache, headache, dizziness or changes to taste. 

Although it is more rare, some people may also experience palpitations, seizures or liver-related symptoms like loss of appetite, dark urine, white stool, or yellow skin or eyes. 

Fluconazole that cause allergic reactions require immediate medical attention. If you experience a reaction, you should stop treatment immediately and proceed to the emergency room, especially if you have symptoms like difficulty breathing, fever, cough, chest pain, burning eyes, blisters, itchy skin or swollen throat, mouth tongue or face. 

Who should not use it 

Fluconazole should not be used in people under the age of 18, in older adults over 60, or in women who are pregnant or breastfeeding. In addition, it should also not be used by people who are allergic to fluconazole or other antifungals like cetoconazole, miconazole, or itraconazole. 

This medication can interfere with the efficacy of oral birth control, and therefore another contraception method should be used when being treated. You should continue to use another method for 1 week after the last dose. Learn more about other birth control options

Diabetics should be cautious when taking fluconazole capsules as they contain sugar in their composition. 

It is important to inform your doctor of all medications you are using, as fluconazole may have interactions with medications like terfenadine, cisapride, astemizole, erythromycin, pimozide or quinidine. 

Frequently asked questions 

Are there fluconazole ointments?

Fluconzole ointment does not exist. This medication is only available in tablet, oral suspension or IV solutions to be administered in the hospital.  

There are other antifungal ointments and creams that can be used topically to complement oral fluconazole. You should only use two antifungals under medical supervision.

Do I need a prescription for fluconazole? 

Fluconazole can be purchased over-the-counter or with a prescription from the doctor. Over-the-counter doses are usually used to treat vaginal yeast infections. Learn more about how vaginal yeast infections are treated. 

Can I drink when taking fluconazole?

Alcohol use in moderation is not contraindicated for fluconazole use. Although it is rare, alcohol use with chronic fluconazole use can cause liver damage and symptoms like fever or skin blisters. However, it is important to note that alcohol can worsen Candida sp. infections, which can make fluconazole treatments less effective.