Drug interactions
Lithium + Methyldopa
Severity: Moderate
Lithium and Methyldopa: 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
Case reports describe lithium toxicity symptoms, such as tremor, confusion and neurologic signs, in patients given methyldopa, sometimes with serum lithium in the usual range. The combination may therefore cause neurotoxicity even without a clear rise in lithium levels.
What this interaction means in plain words
Lithium and Methyldopa 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; Methyldopa belongs to Cardiovascular.
Why it happens
The mechanism is not established; possible additive central effects on neurotransmission.
What to do
Avoid the combination if possible, or monitor for neurologic signs of lithium toxicity and check serum lithium. Consider another antihypertensive if symptoms appear.
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 Methyldopa
- Methyldopa + Tranylcypromine Contraindicated
- Iobenguane i + Methyldopa Major
- Lofexidine + Methyldopa Major
- Methyldopa + Pexidartinib Major
- Methyldopa + Pretomanid Major
- Methyldopa + Thioridazine Major
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 Methyldopa?
MediHelp rates the interaction as moderate. Lithium and Methyldopa 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. Case reports describe lithium toxicity symptoms, such as tremor, confusion and neurologic signs, in patients given methyldopa, sometimes with serum lithium in the usual range. The combination may therefore cause neurotoxicity even without a clear rise in lithium levels.
How serious is the interaction between Lithium and Methyldopa?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible, or monitor for neurologic signs of lithium toxicity and check serum lithium. Consider another antihypertensive if symptoms appear.
What other medicines interact with Methyldopa?
MediHelp also lists interactions of Methyldopa with, for example, Tranylcypromine, Iobenguane i, Lofexidine. The full list is on the Methyldopa page.
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