Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Systemic Antifungal — Onychomycosis / Tinea

Itraconazole

Brand names: Sporanox, Itrimul

Itraconazole is a triazole antifungal used for dermatophyte (e.g. nail), candidal and some systemic fungal infections.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

DOSAGE AND ADMINISTRATION Itraconazole capsules should be taken with a full meal to ensure maximal absorption. Itraconazole capsules must be swallowed whole. Itraconazole capsule is a different preparation than itraconazole Oral Solution and should not be used interchangeably. Treatment of Blastomycosis and Histoplasmosis: The recommended dose is 200 mg once daily (2 capsules). If there is no obvious improvement, or there is evidence of progressive fungal disease, the dose should be increased in 100-mg increments to a maximum of 400 mg daily. Doses above 200 mg/day should be given in two divided doses. Treatment of Aspergillosis: A daily dose of 200 to 400 mg is recommended. Treatment in …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-03-10. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It inhibits fungal ergosterol synthesis, impairing the fungal cell membrane.

Prescribing in practice

  • It is a strong CYP3A4 inhibitor with many serious interactions (e.g. with some statins, certain other drugs) — review co-medication.
  • It has a negative inotropic effect — avoid in heart failure or a history of it.
  • Hepatotoxicity can occur; capsule absorption needs stomach acid and food (the oral solution differs).

Monitoring

Consider liver function with longer courses; review interactions and cardiac status.

Counselling the patient

  • Take capsules with food.
  • Tell your clinician about all other medicines, as itraconazole interacts with many.
  • Report breathlessness or ankle swelling, or yellowing of the skin/eyes.

Evidence & guidelines

Used for dermatophyte, candidal and some systemic fungal infections, with attention to interactions and cardiac effects.

Reference: MHRA Drug Safety Update (Heart failure); BAD Onychomycosis Guidelines 2014; NICE CKS Fungal Nail Infection; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Drugs
Pathways