Lonafarnib and Dihydroergotamine Injection: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Lonafarnib
Dihydroergotamine Injection
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased dihydroergotamine exposure and an increased risk of dihydroergotamine-related adverse effects
Interaction Deep Dive
Concomitant use of dihydroergotamine and a strong CYP3A4 inhibitor is contraindicated because of increased dihydroergotamine exposure which increases risk of vasospasm that may lead to cerebral ischemia and/or ischemia of the extremities1234.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of dihydroergotamine
Literature reports
2 reports — tap to read
a) There have been a few reports of serious adverse events associated with the coadministration of dihydroergotamine and potent CYP3A4 inhibitors, resulting in vasospasm that led to cerebral ischemia and/or ischemia of the extremities 4.
b) In a drug interaction study, coadministration of dihydroergotamine with itraconazole (CYP3A4 inhibitor) increased dihydroergotamine plasma exposure by 14% for Cmax and 19% for AUC while the plasma exposures (Cmax and AUC (0-inf)) of 8-beta-hydroxy dihydroergotamine (8-OH-DHE, active metabolite) were increased by approximately 4-fold and 3-fold, respectively 1.
Common questions
Can I take Lonafarnib and Dihydroergotamine Injection together?
Increased dihydroergotamine exposure and an increased risk of dihydroergotamine-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lonafarnib and Dihydroergotamine Injection interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Lonafarnib or Dihydroergotamine Injection need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (4)
- Product Information: ATZUMI(R) nasal powder, dihydroergotamine nasal powder. Satsuma Pharmaceuticals (per Manufacturer), Durham, NC, 2025. DailyMed
- Product Information: BREKIYA(R) subcutaneous injection, dihydroergotamine mesylate subcutaneous injection. Amneal Pharmaceuticals (Per Manufacturer), Bridgewater, NJ, 2025. DailyMed
- Product Information: TRUDHESA(TM) nasal spray, dihydroergotamine mesylate nasal spray. Impel NeuroPharma Inc (per DailyMed), Seattle, WA, 2021. DailyMed
- Product Information: Migranal(R) nasal spray, dihydroergotamine mesylate nasal spray. Bausch Health US LLC (per FDA), Bridgewater, NJ, 2022. DailyMed
Keep reading about Lonafarnib
Keep reading about Dihydroergotamine Injection
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