PlainMeds provides educational information only. This is not medical advice. Always consult your doctor or pharmacist.

itraconazole vs ketoconazole

Side-by-side comparison of itraconazole 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

Although many of the clinical drug interactions in Table 1 are based on information with a similar azole antifungal, ketoconazole, these interactions are expected to occur with itraconazole. Although many of the clinical drug interactions in Table 2 are based on information with a similar azole antifungal, ketoconazole, these interactions are expected to occur with itraconazole.

Recommendation: Your doctor should monitor you closely for side effects since these two drugs have very similar effects on the body.

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

Itraconazole capsules are an antifungal medicine. They treat fungal infections in your body.

ketoconazole

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

What It Treats
itraconazole

Itraconazole treats fungal infections like blastomycosis, histoplasmosis, and aspergillosis. It can help both people with healthy immune systems and those with weakened immune systems. It also treats onychomycosis, a fungal infection of the toenails or fingernails.

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
itraconazole

Itraconazole stops fungi from growing. It does this by interfering with the production of a substance fungi need to build their cell membranes. This eventually kills the fungus and clears 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
itraconazole
  • Nausea
  • Rash
  • Headache
ketoconazole

No common side effects listed.

FAERS Reports
itraconazole
  • Interaction with another medicine 1,118
  • Medicine not working 1,100
  • Using the medicine for something it's not approved for 606
  • Fever 570
  • Difficulty breathing 472
ketoconazole
  • The medicine did not work 1,582
  • Using the medicine for something it's not approved for 1,174
  • Feeling tired 929
  • Itching 902
  • Feeling sick to your stomach 834
Serious Warnings
itraconazole

Itraconazole can cause congestive heart failure. You should not take this medicine if you have heart problems. Itraconazole can also interact with many other medicines. Some of these interactions can be dangerous or even fatal. Check with your doctor about all the medicines you take.

ketoconazole

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

Pregnancy
itraconazole

You should not take itraconazole if you are pregnant or plan to become pregnant. It can harm your unborn baby. Talk to your doctor about safe alternatives.

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 itraconazole vs ketoconazole Comparison

itraconazole 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, itraconazole has 3,866 submissions while ketoconazole has 5,421. 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 both drugs are in the same family and work in similar ways, which can cause them to build up in your body or increase side effects.. 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 itraconazole and ketoconazole — 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.