Dexamethasone and Ivacaftor interaction
Dexamethasone and Ivacaftor: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Dexamethasone (Hemady) label · effective 2026-01-09
• Avoid concomitant use of strong CYP3A4 inhibitors or inducers.
Avoid coadministration of strong CYP3A4 inhibitors or consider alternative medication that are not strong CYP3A4 inhibitors.
If concomitant use of strong CYP3A4 inhibitors cannot be avoided, closely monitor for adverse drug reactions.
( 7.2 ) 7.1 Effect of Other Drugs on HEMADY Strong CYP3A4 inhibitors Coadministration of strong and moderate CYP3A4 inhibitors increased dexamethasone exposure [see Clinical Pharmacology ( 12.3 )] , which may increase the risk of adverse reactions [see Warnings and Precautions ( 5 ) and Adverse Reactions ( 6 )] .
From the Ivacaftor (Kalydeco) label · effective 2026-03-23
Concomitant Use with CYP3A Inducers Use of KALYDECO with strong CYP3A inducers, such as rifampin, substantially decreases the exposure of ivacaftor, which may reduce the therapeutic effectiveness of KALYDECO.
Although other risk factors were present in some cases (such as corticosteroid use and/or exposure to radiation), a possible risk attributable to KALYDECO cannot be excluded.
Inducers of CYP3A Co-administration with rifampin, a strong CYP3A inducer, significantly decreased ivacaftor exposure (AUC) by approximately 9-fold.
Use with CYP3A inducers: Concomitant use with strong CYP3A inducers (e.g., rifampin, St.
Therefore, co-administration of KALYDECO with strong CYP3A inducers (e.g., rifampin, St.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.