What Is Ketoconazole? Uses, Dosage, and What You Need to Know in 2026

Ketoconazole is a broad-spectrum antifungal medication that has been in use since the early 1980s. It's a member of the azole antifungal drug class and works by disrupting the fungal cell membrane. Available in multiple forms — oral tablet, cream, shampoo, foam, and gel — it treats a wide range of fungal conditions from everyday dandruff to serious systemic infections. Here's a comprehensive overview of what ketoconazole is, what it treats, how to take it, and what you need to know about its risks in 2026.

Ketoconazole Brand Names and Available Forms

Ketoconazole is the generic name. Brand names include:

Nizoral: Brand name for both the oral 200 mg tablet and the 2% prescription shampoo

Nizoral A-D: Over-the-counter 1% anti-dandruff shampoo — no prescription required

Extina: Ketoconazole 2% foam for seborrheic dermatitis

Xolegel / Ketodan: Ketoconazole 2% gel for seborrheic dermatitis of the scalp

Kuric: Another brand of ketoconazole 2% cream

What Conditions Does Ketoconazole Treat?

Topical ketoconazole is approved for:

Seborrheic dermatitis (dandruff, flaking, scalp or facial redness)

Tinea versicolor (pityriasis versicolor) — a patchy skin discoloration caused by Malassezia yeast

Ringworm (tinea corporis)

Athlete's foot (tinea pedis)

Jock itch (tinea cruris)

Cutaneous candidiasis (skin yeast infections)

Oral ketoconazole tablet (last resort) is approved for:

Blastomycosis

Coccidioidomycosis (Valley Fever)

Histoplasmosis

Chromomycosis

Paracoccidioidomycosis

These systemic infections are only treated with oral ketoconazole when preferred antifungal therapies (like itraconazole or fluconazole) are not available or not tolerated. The FDA also approved oral ketoconazole for patients with severe skin/nail infections that don't respond to griseofulvin, though this is rarely used in modern practice.

Ketoconazole Dosage Guide

Oral tablet (200 mg):

Adults: 200–400 mg once daily with food

Duration: 1–6 months depending on infection type

Take at the same time each day; do not skip doses

2% Topical cream:

Apply to affected and surrounding area once daily

Tinea versicolor: 2 weeks; Athlete's foot: 6 weeks; Seborrheic dermatitis: 4 weeks or until clear

2% Shampoo (prescription):

Tinea versicolor: Apply to affected skin and scalp, leave on 5 minutes, rinse — one-time application

Seborrheic dermatitis: Use twice weekly for 4 weeks, then once every 1–2 weeks for maintenance

1% OTC shampoo (Nizoral A-D):

Dandruff control: Use every 3–4 days for up to 8 weeks; for maintenance, use as needed

Is Ketoconazole Safe? Key Safety Information

Topical ketoconazole is generally safe with a good tolerability profile. The story is very different for the oral tablet:

Black box warning: Serious liver injury (including deaths) and QT prolongation

Not a first-line treatment: The FDA requires oral ketoconazole to be used only as a last resort

Extensive drug interactions: Over 300 drug interactions documented; requires full medication review before prescribing

Pregnancy: Category C — use only if the benefit justifies the potential risk to the fetus

Not for children under 2: Safety and efficacy not established in children under 2 years old

The Bottom Line

Ketoconazole is a versatile antifungal with both topical and oral forms. For most patients, it's prescribed as a topical product for skin and scalp conditions, where it works well with minimal side effects. Oral ketoconazole is reserved for serious systemic infections that don't respond to safer alternatives. For a deeper look at how the drug works at the cellular level, see: How Does Ketoconazole Work? Mechanism of Action Explained.

If you have a ketoconazole prescription and need help finding it in stock, medfinder can help you find a pharmacy near you that can fill it today.