Drug interactions
Toremifene + Voriconazole
Severity: Major
Toremifene and Voriconazole: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Toremifene is metabolized by CYP3A4 and itself prolongs the QT interval, and voriconazole also prolongs QT while raising toremifene levels. The combination increases the risk of torsades de pointes.
What this interaction means in plain words
Toremifene and Voriconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Toremifene belongs to Endocrine; Voriconazole belongs to Anti Fungals.
Why it happens
CYP3A4 inhibition raises toremifene exposure, with additive QT prolongation from both drugs.
What to do
Avoid the combination where possible, as toremifene labeling advises against strong CYP3A4 inhibitors with QT risk. If unavoidable, monitor ECG and electrolytes closely.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Voriconazole
- Avanafil + Voriconazole Contraindicated
- Butabarbital + Voriconazole Contraindicated
- Carbamazepine + Voriconazole Contraindicated
- Conivaptan + Voriconazole Contraindicated
- Dihydroergotamine intranasal + Voriconazole Contraindicated
- Dihydroergotamine + Voriconazole Contraindicated
Other interactions of Toremifene
- Amiodarone + Toremifene Contraindicated
- Dronedarone + Toremifene Contraindicated
- Nilotinib + Toremifene Contraindicated
- Pimozide + Toremifene Contraindicated
- Quinidine + Toremifene Contraindicated
- Ribociclib + Toremifene Contraindicated
Frequently asked questions
Can I take Toremifene with Voriconazole?
MediHelp rates the interaction as major. Toremifene and Voriconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Toremifene is metabolized by CYP3A4 and itself prolongs the QT interval, and voriconazole also prolongs QT while raising toremifene levels. The combination increases the risk of torsades de pointes.
How serious is the interaction between Toremifene and Voriconazole?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible, as toremifene labeling advises against strong CYP3A4 inhibitors with QT risk. If unavoidable, monitor ECG and electrolytes closely.
What other medicines interact with Voriconazole?
MediHelp also lists interactions of Voriconazole with, for example, Avanafil, Butabarbital, Carbamazepine. The full list is on the Voriconazole page.
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