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fluconazole vs isavuconazonium

Side-by-side comparison of fluconazole and isavuconazonium Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

Drug Class
fluconazole Azole Antifungal
isavuconazonium Azole Antifungal
Type
fluconazole Prescription
isavuconazonium Prescription
Summary
fluconazole

Fluconazole is an antifungal medicine. It is used to treat infections caused by fungus.

isavuconazonium

Cresemba is an antifungal medicine. It is used to treat serious fungal infections in adults and children.

What It Treats
fluconazole

Fluconazole treats vaginal yeast infections. It also treats yeast infections in the mouth and esophagus. Fluconazole can also treat urinary tract infections, peritonitis, systemic Candida infections, and pneumonia. It can also treat cryptococcal meningitis. Fluconazole can also prevent candidiasis in patients undergoing bone marrow transplantation.

isavuconazonium

Cresemba treats invasive aspergillosis and invasive mucormycosis. These are serious infections caused by different types of fungi. Cresemba is available as an injection for those 1 year and older. Cresemba capsules are for those 6 years and older who weigh at least 35 pounds.

How It Works
fluconazole

Fluconazole works by stopping the growth of fungi. It blocks the fungus from producing a substance it needs to grow. This helps to clear up the infection.

isavuconazonium

Cresemba belongs to a class of drugs called azole antifungals. It works by stopping the growth of the fungi. This helps your body fight off the infection.

Common Side Effects
fluconazole
  • Headache
  • Nausea
  • Abdominal pain
isavuconazonium
  • Nausea
  • Vomiting
  • Diarrhea
  • Headache
  • Changes in liver tests
FAERS Reports
fluconazole
  • Medicine not working 4,932
  • Using medicine for unapproved purpose 4,329
  • Fever 4,121
  • Feeling sick to your stomach 3,695
  • Loose stools 3,536
isavuconazonium
  • Using the medicine for a condition it is not approved for 926
  • Death 310
  • Feeling sick to your stomach 143
  • Fever with low white blood cell count 135
  • Medicine not working 125
Serious Warnings
fluconazole

Coadministration of other drugs known to prolong the QT interval and which are metabolized via the enzyme CYP3A4 such as erythromycin, pimozide, and quinidine are contraindicated in patients receiving fluconazole.

isavuconazonium

Cresemba can cause serious liver problems. Your doctor will check your liver function before and during treatment. Cresemba can also cause allergic reactions. Tell your doctor right away if you have any signs of a reaction, like trouble breathing or skin rash. Cresemba can harm an unborn baby. Use birth control while taking this medicine.

Pregnancy
fluconazole

Tell your doctor if you are pregnant or plan to become pregnant. Fluconazole may not be safe for your baby. Talk to your doctor about breastfeeding while taking fluconazole.

isavuconazonium

Cresemba can harm your unborn baby. Tell your doctor if you are pregnant or plan to become pregnant. Do not breastfeed while taking Cresemba.

Also Compare — Nearby Drugs

How to Read This fluconazole vs isavuconazonium Comparison

fluconazole is classified in the Azole Antifungal drug class, while isavuconazonium sits within the Azole Antifungal class. Because both drugs share the same classification, they are often considered interchangeable in theory — but clinical outcomes rarely track that cleanly. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, fluconazole has 20,613 submissions while isavuconazonium has 1,639. Those figures reflect cumulative reporting volume — not per-patient risk — so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between fluconazole and isavuconazonium — always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.