Drug interactions
Levoketoconazole + Phenytoin
Severity: Major
Levoketoconazole and Phenytoin: 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-type azoles may raise phenytoin levels, risking toxicity, while phenytoin can also reduce ketoconazole exposure through induction. The net effect can compromise both drugs.
What this interaction means in plain words
Levoketoconazole and Phenytoin 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.
Levoketoconazole belongs to Endocrine; Phenytoin belongs to Central Nervous System.
Why it happens
Levoketoconazole inhibits CYP2C9 metabolism of phenytoin, while phenytoin induces CYP3A4 metabolism of levoketoconazole.
What to do
Monitor phenytoin levels and toxicity signs and reduce the dose if needed. Monitor cortisol control and consider an alternative to phenytoin, since strong inducers reduce levoketoconazole efficacy.
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 Phenytoin
- Artemether / lumefantrine + Phenytoin Contraindicated
- Bictegravir + Phenytoin Contraindicated
- Cabotegravir + Phenytoin Contraindicated
- Doravirine + Phenytoin Contraindicated
- Elbasvir / grazoprevir + Phenytoin Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Phenytoin Contraindicated
Other interactions of Levoketoconazole
- Alfuzosin + Levoketoconazole Contraindicated
- Alprazolam + Levoketoconazole Contraindicated
- Amiodarone + Levoketoconazole Contraindicated
- Avanafil + Levoketoconazole Contraindicated
- Cisapride + Levoketoconazole Contraindicated
- Clarithromycin + Levoketoconazole Contraindicated
Frequently asked questions
Can I take Levoketoconazole with Phenytoin?
MediHelp rates the interaction as major. Levoketoconazole and Phenytoin 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-type azoles may raise phenytoin levels, risking toxicity, while phenytoin can also reduce ketoconazole exposure through induction. The net effect can compromise both drugs.
How serious is the interaction between Levoketoconazole and Phenytoin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor phenytoin levels and toxicity signs and reduce the dose if needed. Monitor cortisol control and consider an alternative to phenytoin, since strong inducers reduce levoketoconazole efficacy.
What other medicines interact with Phenytoin?
MediHelp also lists interactions of Phenytoin with, for example, Artemether / lumefantrine, Bictegravir, Cabotegravir. The full list is on the Phenytoin page.
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