Drug interactions
Olanzapine + Peginterferon alfa 2a
Severity: Moderate
Olanzapine and Peginterferon alfa 2a: moderate 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
Peginterferon alfa 2a can suppress CYP1A2 activity, which may raise olanzapine concentrations. Patients may experience more sedation, orthostatic hypotension or other dose-related adverse effects.
What this interaction means in plain words
Olanzapine and Peginterferon alfa 2a can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Olanzapine belongs to Central Nervous System; Peginterferon alfa 2a belongs to Anti Virals.
Why it happens
Interferon-mediated downregulation of hepatic CYP1A2 reduces olanzapine clearance.
What to do
Monitor for sedation, hypotension and anticholinergic effects when starting or stopping peginterferon. Reduce the olanzapine dose if adverse effects emerge.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Peginterferon alfa 2a
Other interactions of Olanzapine
Frequently asked questions
Can I take Olanzapine with Peginterferon alfa 2a?
MediHelp rates the interaction as moderate. Olanzapine and Peginterferon alfa 2a can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Peginterferon alfa 2a can suppress CYP1A2 activity, which may raise olanzapine concentrations. Patients may experience more sedation, orthostatic hypotension or other dose-related adverse effects.
How serious is the interaction between Olanzapine and Peginterferon alfa 2a?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for sedation, hypotension and anticholinergic effects when starting or stopping peginterferon. Reduce the olanzapine dose if adverse effects emerge.
What other medicines interact with Peginterferon alfa 2a?
MediHelp also lists interactions of Peginterferon alfa 2a with, for example, Clozapine, Deferiprone, Hydroxyurea. The full list is on the Peginterferon alfa 2a page.
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