Dihydroergotamine and Posaconazole interaction
Dihydroergotamine and Posaconazole: 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 Dihydroergotamine (Dihydroergotamine Mesylate) label · effective 2026-05-26
WARNING: PERIPHERAL ISCHEMIA FOLLOWING COADMINISTRATION WITH POTENT CYP3A4 INHIBITORS Serious and/or life-threatening peripheral ischemia has been associated with the coadministration of dihydroergotamine with potent CYP3A4 inhibitors including protease inhibitors and macrolide antibiotics.
Because CYP3A4 inhibition elevates the serum levels of dihydroergotamine, the risk for vasospasm leading to cerebral ischemia and/or ischemia of the extremities is increased.
CONTRAINDICATIONS There have been a few reports of serious adverse events associated with the coadministration of dihydroergotamine and potent CYP3A4 inhibitors, such as protease inhibitors and macrolide antibiotics, resulting in vasospasm that led to cerebral ischemia and/or ischemia of the extremities.
The use of potent CYP3A4 inhibitors (i.e., ritonavir, nelfinavir, indinavir, erythromycin, clarithromycin, troleandomycin, ketoconazole, itraconazole) with dihydroergotamine is, therefore, contraindicated (see WARNINGS, CYP3A4 Inhibitors ).
The use of potent CYP3A4 inhibitors with dihydroergotamine should therefore be avoided (see CONTRAINDICATIONS ).
From the Posaconazole (NOXAFIL) label · effective 2026-02-13
Use with Ergot Alkaloids Noxafil may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism [see Drug Interactions (7.2) ].
Prevention or Management Ergotamine, Dihydroergotamine Concomitant use with posaconazole is contraindicated.
Posaconazole may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism.
Ergot Alkaloids Mechanism and Clinical Effect(s) Most of the ergot alkaloids are CYP3A4 substrates.
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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.