Drug interactions
Ketoconazole + Trazodone
Severity: Major
Ketoconazole and Trazodone: 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
Ketoconazole raises trazodone concentrations, causing more sedation, hypotension and serotonergic effects. Both drugs also prolong the QT interval, adding to arrhythmia risk.
What this interaction means in plain words
Ketoconazole and Trazodone 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.
Ketoconazole belongs to Anti Fungals; Trazodone belongs to Central Nervous System.
Why it happens
CYP3A4 inhibition reduces trazodone clearance, with additive QT prolongation.
What to do
Use a lower trazodone dose and monitor for sedation, hypotension and ECG changes. Consider an alternative antifungal or antidepressant if QT risk factors exist.
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 Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Other interactions of Trazodone
- Arsenic trioxide + Trazodone Contraindicated
- Ibutilide + Trazodone Contraindicated
- Isocarboxazid + Trazodone Contraindicated
- Levoketoconazole + Trazodone Contraindicated
- Methylene blue + Trazodone Contraindicated
- Phenelzine + Trazodone Contraindicated
Frequently asked questions
Can I take Ketoconazole with Trazodone?
MediHelp rates the interaction as major. Ketoconazole and Trazodone 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. Ketoconazole raises trazodone concentrations, causing more sedation, hypotension and serotonergic effects. Both drugs also prolong the QT interval, adding to arrhythmia risk.
How serious is the interaction between Ketoconazole and Trazodone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a lower trazodone dose and monitor for sedation, hypotension and ECG changes. Consider an alternative antifungal or antidepressant if QT risk factors exist.
What other medicines interact with Ketoconazole?
MediHelp also lists interactions of Ketoconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Ketoconazole page.
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