Drug interactions
Methadone + Olanzapine
Severity: Moderate
Methadone and Olanzapine: 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
Both drugs can prolong the QTc interval, and olanzapine also adds sedation and respiratory depressant effects with opioids. Together they raise the risk of arrhythmia and excess sedation.
What this interaction means in plain words
Methadone and Olanzapine 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.
Methadone belongs to Musculoskeletal; Olanzapine belongs to Central Nervous System.
Why it happens
Additive QT prolongation and additive CNS depression.
What to do
Check a baseline ECG and electrolytes, and monitor the QTc and sedation after changes. Use the lowest effective doses.
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 Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Lefamulin + Methadone Contraindicated
Other interactions of Olanzapine
Frequently asked questions
Can I take Methadone with Olanzapine?
MediHelp rates the interaction as moderate. Methadone and Olanzapine 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. Both drugs can prolong the QTc interval, and olanzapine also adds sedation and respiratory depressant effects with opioids. Together they raise the risk of arrhythmia and excess sedation.
How serious is the interaction between Methadone and Olanzapine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check a baseline ECG and electrolytes, and monitor the QTc and sedation after changes. Use the lowest effective doses.
What other medicines interact with Methadone?
MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone page.
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