isavuconazonium vs ketoconazole

PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.

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

minor Known Drug Interaction

Drug(s) Affecting Pharmacokinetics of CRESEMBA Recommendation Comments Ketoconazole Contraindicate coadministration of all potent CYP3A4 inhibitors There is more than a 5-fold increase in exposure of isavuconazole upon coadministration with ketoconazole [see Clinical Pharmacology ( 12.3 )] .

Drug Class
isavuconazonium Azole Antifungal
ketoconazole Azole Antifungal
Type
isavuconazonium Prescription
ketoconazole Over-the-Counter
Summary
isavuconazonium

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

ketoconazole

Ketoconazole shampoo is an antifungal medicine. It treats a fungal infection on your skin.

What It Treats
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.

ketoconazole

This shampoo treats tinea versicolor, a fungal infection. This infection can cause patches on your skin that are lighter or darker than the surrounding skin. These patches may appear on your trunk, neck, arms, and upper thighs.

How It Works
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.

ketoconazole

Ketoconazole is an antifungal medicine. It works by stopping the growth of the fungus. This helps to clear up the infection.

Common Side Effects
isavuconazonium
  • Nausea
  • Vomiting
  • Diarrhea
  • Headache
  • Changes in liver tests
ketoconazole

No common side effects listed.

FAERS Reports
isavuconazonium
  • Death 310
  • Nausea 143
  • Febrile Neutropenia 135
  • Pyrexia 125
  • Pneumonia 114
ketoconazole
  • Fatigue 929
  • Pruritus 902
  • Nausea 834
  • Rash 802
  • Diarrhoea 760
Serious Warnings
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.

ketoconazole

You should not use this shampoo if you are allergic to ketoconazole or any of the other ingredients.

Pregnancy
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.

ketoconazole

It is not known if ketoconazole shampoo can harm an unborn baby. Talk to your doctor if you are pregnant or breastfeeding before using this medicine.

Also Compare, Nearby Drugs

How to Read This isavuconazonium vs ketoconazole Comparison

isavuconazonium is classified in the Azole Antifungal drug class, while ketoconazole 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 split between OTC and prescription status, which affects access and supervision.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, isavuconazonium has 827 submissions while ketoconazole has 4,227. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to ketoconazole stops your body from breaking down isavuconazonium, which can lead to very high levels of the drug in your system. this increases the risk of serious side effects.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for isavuconazonium or ketoconazole.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.