Reviewed on 12/16/2021

What Is Itraconazole and How Does It Work?

Itraconazole is a prescription medication used to treat fungal infections of the lungs, mouth or throat, tonenails or fingernails. 

Itraconazole is available under the following different brand names: Sporanox, Onmel, Tosura. 

Dosages of Itraconazole

Adult dosage


Oral solution

  • 10mg/mL (Sporanox, generic)


  • 200mg (Onmel)

Life-threatening Infections 

Adult dosage


  • Loading dose: 200 mg (2 capsules) orally three times daily (600 mg/day) for the first 3 days, followed by recommended dosing based on indication


  • Loading dose: 130 mg (2x65 mg capsules) orally three times daily (390 mg/day) for the first 3 days, followed by recommended dosing based on indication. 
  • Continue for a minimum of 3 months and until active fungal infection has subsided; an inadequate period of treatment may lead to recurrence of active infection


Adult dosage


  • 200 mg orally once day
  • If no improvement, or evidence of progressive fungal disease, increase does in 100-mg increments to a maximum of 400 mg/day
  • Divided doses over 200 mg/day into 2 doses


  • 130 mg orally once daily
  • If no improvement, or evidence of progressive fungal disease, increase dose in 65 mg increments to a maximum of 260 mg/day (130 mg twice daily)
  • Dived doses over 130 mg/day into 2 doses


Adult dosage


  • 200-400 mg/day orally; may be used in combination with corticosteroids


  • 130 mg orally once per day or twice per day


Adult dosage


  • 200 mg orally once per day
  • If no improvement, or evidence of progressive fungal disease, increase dose in 100-mg increments to a maximum of 400 mg/day
  • Divide doses over 200 mg/day into 2 doses


  • 130 mg orally once per day
  • If no improvement, or evidence of progressive fungal disease, increase dose in 65 mg increments to a maximum of 260 mg/day (130 mg twice daily)
  • Divide doses over 130 mg/day into 2 days


Adult dosage

  • Fingernails (Sporanox only): 2 treatment pulses, each consisting of 200 mg every 12 hours for 1 week; pulses are separated by a 3-week period without Sporonax
  • Toenails, with or without fingernail involvement (Sporanox, Onmel): 200 mg/day orally for 12 weeks


Adult dosage

Esophageal candidiasis

  • 100 mg (10 mL) orally once daily for a minimum of 3 weeks; continue treatment for 2 weeks following resolution of symptoms
  • Doses less than 200 mg/day (20 mL) may be used based on medical judgment of the patient’s response to therapy

Oropharyngeal candidiasis

  • Oral solution only: 200 mg (20 mL) orally once daily for 1-2 weeks; signs and symptoms of oropharyngeal candidiasis generally resolve within several days
  • Unresponsive/refractory to fluconazole: 100 mg (10 mL) orally twice daily
  • Clinical response will be seen in 2-4 weeks
  • May be expected to relapse shortly after discontinuing therapy
  • Limited data on safety of long-term use over (6 months) of oral solution are available at this time

Dosage Considerations – Should be Given as Follows: 

  • See "Dosages."

What Are Side Effects Associated with Using Itraconazole?

Common side effects of Itraconazole include:

  • headache, 
  • dizziness, 
  • drowsiness, 
  • tiredness, 
  • increased blood pressure, 
  • rash, 
  • itching, 
  • nausea, 
  • vomiting, 
  • stomach pain, 
  • diarrhea, 
  • constipation, 
  • swelling, 
  • abnormal liver function or blood tests, 
  • fever, 
  • muscle or joint pain, 
  • unusual or unpleasant taste in your mouth, 
  • hair loss, 
  • impotence
  • erection problems, and
  • changes in your menstrual periods

Serious side effects of Itraconazole include:

  • hives, 
  • severe skin rash, 
  • tingling in your arms or legs, 
  • difficulty breathing, 
  • swelling of your face, lips, tongue, or throat, 
  • tiredness, 
  • shortness of breath, 
  • cough with mucus, 
  • fast heartbeats, 
  • swelling, 
  • rapid weight gain, 
  • sleep problems, 
  • confusion, 
  • lightheadedness
  • blurred vision, 
  • double vision, 
  • ringing in your ears, 
  • problems with hearing, 
  • numbness or tingly feeling, 
  • loss of bladder control, 
  • little or no urinating, 
  • pain or burning when you urinate, 
  • leg cramps, 
  • constipation, 
  • irregular heartbeats, 
  • fluttering in your chest, 
  • increased thirst or urination, 
  • muscle weakness or limp feeling, 
  • severe pain in your upper stomach spreading to your back, 
  • nausea, 
  • vomiting, 
  • upper stomach pain, 
  • loss of appetite, 
  • dark urine, 
  • clay-colored stools, and
  • yellowing of the skin or eyes (jaundice)

Rare side effects of Itraconazole include:

  • none 

This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

What Other Drugs Interact with Itraconazole?

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them.  Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first

  • Itraconazole has severe interactions with at least 43 other drugs. 
  • Itraconazole has serious interactions with at least 173 other drugs. 
  • Itraconazole has moderate interactions with at least 264 other drugs. 
  • Itraconazole has minor interactions with at least 44 other drugs. 

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drugs interactions. Therefore, before using this drug, tell your doctor or pharmacist of all the drugs you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

What Are Warnings and Precautions for Itraconazole?


  • Hypersensitivity
  • Contraindicated with certain CYP3A4 substrate drugs (see Black Box Warnings)
  • Coadministration with colchicine, fesoterodine, and solifenacin in patients with varying degrees of renal or hepatic impairment
  • Coadministration with eliglustat in patients who are poor or intermediated CYP2D6 metabolizers, or if coadministered with strong or moderate CYP2D6 inhibitors
  • Increased plasma concentrations resulting from coadministration with itraconazole of some of the aforementioned drugs can lead to QT prolongation and ventricular tachyarrhythmias
  • Treatment of onychomycosis in women who are pregnant or plan to become pregnant

Effects of drug abuse

  • None

Short-Term Effects

  • See “What Are Side Effects Associated with Using Itraconazole?”

Long-Term Effects

  • See “What Are Side Effects Associated with Using Itraconazole?”


  • Cases of serious hepatotoxicity, including liver failure and death, reported; discontinue if liver disease develops, and perform liver function tests; readministration discouraged
  • Prolongs QT interval; caution with concurrent QT-prolonging drugs or congenital long QT (see Black Box Warnings for drugs contraindicated for use with itraconazole)
  • Can cause or exacerbated CHF; not for the treatment of other indications in patients with evidence of ventricular dysfunction unless benefit clearly outweighs risks; risk factors include cardiac disease such as ischemic and valvular disease; significant pulmonary disease such as chronic obstructive pulmonary disease; and renal failure and other edematous disorders; monitor for signs and symptoms of CHF during treatment; if signs or symptoms of CHF appear or worsen during administration, reassess benefit-risk of continuing treatment
  • Calcium channel blockers can have negative inotropic effects which may be additive to those of itraconazole. when co-administering itraconazole and calcium channel blockers, monitor carefully for signs and symptoms of CHF during treatment due to an increased risk of CHF
  • Life-threatening cardiac arrhythmias and/or sudden death reported when coadministered with drugs that are CYP3A4 substrates and are associated with arrhythmias with increased systemic exposure (eg, pimozide, methadone, quinidine)
  • May cause CNS depression, which may impair mental alertness and subsequently impair ability to operate heavy machinery or performing hazardous tasks
  • Oral capsule and oral solution are not bioequivalent; do not use interchangeably
  • Parenteral form is incompatible with most aqueous solutions; use dedicated line, and do not mix with other drugs in any way
  • If peripheral neuropathy occurs that may be attributable to itraconazole, discontinue treatment
  • If cystic fibrosis patient does not respond to itraconazole, consider switching to alternative therapy; large differences in itraconazole pharmacokinetic parameters observed in cystic fibrosis patients
  • Transient or permanent hearing loss reported in patients receiving treatment with itraconazole; several reports included concurrent administration of quinidine, which is contraindicated; the hearing loss usually resolves when treatment is stopped but can persist in some patients
  • Caution with renal impairment; data are limited
  • Absorption of itraconazole capsules is reduced when gastric acidity reduced; administer capsules with acidic beverage in patients with reduced gastric acidity and do not administer concomitantly with acid-suppressive therapy; monitor for response
  • Only oral solution shown to be effective in oral/esophageal candidiasis; oral solution not recommended in patients at immediate risk for systemic candidiasis
  • Itraconazole should not be used to treat voriconazole-refractory aspergillosis; both agents may share resistance mechanisms

Pregnancy and Lactation

  • There are no data on exposure to itraconazole during pregnancy
  • Published epidemiologic studies of women exposed to short courses of treatment with itraconazole in the first trimester of pregnancy have reported no risk of major birth defects overall and inconclusive findings on the risk of miscarriage
  • Drug should be used for treatment of systemic fungal infections in pregnancy only if benefit outweighs potential risk; therapy should not be administered for treatment of onychomycosis to pregnant patients or to women contemplating pregnancy; drug should not be administered to women of childbearing potential for treatment of onychomycosis unless they are using effective measures to prevent pregnancy and they begin therapy on the second or third day following the onset of menses; highly effective contraception should be continued throughout therapy and for 2 months following the end of treatment
  • Itraconazole is excreted in human milk
  • No data on the amount of itraconazole in human milk, the effects on the breastfed child, or the effects on milk production
  • Developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for itraconazole and any potential adverse effects on the breastfed child from itraconazole or from underlying maternal condition
Medscape. Itraconazole.

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