Drug interactions
Lithium + Methadone
Severity: Moderate
Lithium and Methadone: 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
Lithium has been associated with QT changes and sinus node dysfunction, and methadone prolongs the QTc interval. Together they may raise the risk of arrhythmia, particularly with toxic lithium levels or electrolyte disturbance.
What this interaction means in plain words
Lithium and Methadone 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.
Lithium belongs to Central Nervous System; Methadone belongs to Musculoskeletal.
Why it happens
Additive effects on cardiac repolarization and conduction.
What to do
Obtain a baseline ECG and repeat after dose changes, keep lithium levels in the therapeutic range, and correct electrolytes.
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 Lithium
- Lithium + Thioridazine Contraindicated
- Lithium + Vandetanib Contraindicated
- Aceclofenac + Lithium Major
- Acemetacin + Lithium Major
- Amisulpride + Lithium Major
- Amlodipine-benazepril + Lithium Major
Frequently asked questions
Can I take Lithium with Methadone?
MediHelp rates the interaction as moderate. Lithium and Methadone 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. Lithium has been associated with QT changes and sinus node dysfunction, and methadone prolongs the QTc interval. Together they may raise the risk of arrhythmia, particularly with toxic lithium levels or electrolyte disturbance.
How serious is the interaction between Lithium and Methadone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and repeat after dose changes, keep lithium levels in the therapeutic range, and correct electrolytes.
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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