What the FDA labels say about taking them together
Busulfan and itraconazole
Busulfan's FDA label of June 27, 2024 names itraconazole in its drug interactions section, and itraconazole's label names busulfan too. The busulfan label: “The concomitant systemic administration of itraconazole to patients receiving high-dose MYLERAN may result in reduced busulfan clearance.”
Check it at the source: the busulfan FDA label on DailyMed (effective June 27, 2024, Eugia US LLC); the itraconazole FDA label on DailyMed (effective July 13, 2026, Janssen Pharmaceuticals, Inc.).
What does the busulfan label say about itraconazole?
Busulfan label, drug interactionsDRUG INTERACTIONS Drugs that Decrease Busulfan Clearance: Metronidazole, itraconazole, iron chelating agents, acetaminophen. ( 7.1 ) Drugs that Increase Busulfan Clearance:
Myleran label (Waylis Therapeutics LLC, January 8, 2025), drug interactionsThe concomitant systemic administration of itraconazole to patients receiving high-dose MYLERAN may result in reduced busulfan clearance (see CLINICAL PHARMACOLOGY).
Source: FDA drug label (Myleran, NDA009386), Waylis Therapeutics LLC, effective January 8, 2025 (SPL set 2da33e5b-dcfb-4cdf-b163-50398e42f41c), via openFDA
Source: FDA drug label (Busulfan), Eugia US LLC, effective June 27, 2024 (SPL set 06883ac0-4b2a-4f26-89bf-512d37b9ba7f), via openFDA; the full label on DailyMed
What does the itraconazole label say about busulfan?
Itraconazole label, drug interactionsExamples of Concomitant Drugs Within Class: Bortezomib Brentuximab-vedotin Busulfan Erlotinib Gefitinib Idelalisib Imatinib Ixabepilone; Prevention or Management: Nintedanib Panobinostat Ponatinib Ruxolitinib Sonidegib Tretinoin (oral) Vandetanib; Monitor for adverse reactions. Concomitant drug dose reduction may be necessary. For idelalisib, see also.
Tolsura label (Mayne Pharma Commercial LLC, April 23, 2025), drug interactionsBortezomib Brentuximab-vedotin Busulfan Erlotinib Gefitinib Idelalisib Imatinib Ixabepilone Nintedanib Panobinostat Ponatinib Ruxolitinib Sonidegib Vandetanib Monitor for adverse reactions.
Source: FDA drug label (Tolsura, NDA208901), Mayne Pharma Commercial LLC, effective April 23, 2025 (SPL set 306352d1-9d5a-49ad-b72d-893b99546861), via openFDA
Source: FDA drug label (SPORANOX), Janssen Pharmaceuticals, Inc., effective July 13, 2026 (SPL set a4d555fa-787c-40fb-bb7d-b0d4f7318fd0), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Busulfan | Itraconazole | |
|---|---|---|
| Labeled for | Leukemia, lymphoma and myeloma | Fungal infections |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | n/a | $0.910 per capsule 100 mg capsule |
| Shortage now | A presentation being discontinued | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once