Drug interactions
Carbamazepine + Lamotrigine
Severity: Moderate
Carbamazepine and Lamotrigine: 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
Carbamazepine lowers lamotrigine concentrations and may reduce seizure control. Neurotoxicity with diplopia, dizziness and ataxia is also reported, possibly from a pharmacodynamic effect.
What this interaction means in plain words
Carbamazepine and Lamotrigine 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.
Carbamazepine belongs to Central Nervous System; Lamotrigine belongs to Central Nervous System.
Why it happens
Carbamazepine induces hepatic glucuronidation (UGT) of lamotrigine, and the two drugs have additive CNS effects.
What to do
Use the lamotrigine dosing schedule for patients on enzyme inducers and monitor for neurotoxicity. Reduce the lamotrigine dose if carbamazepine is withdrawn.
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 Carbamazepine
- Artemether / lumefantrine + Carbamazepine Contraindicated
- Cabotegravir + Carbamazepine Contraindicated
- Carbamazepine + Delamanid Contraindicated
- Carbamazepine + Dienogest / estradiol valerate Contraindicated
- Carbamazepine + Doravirine Contraindicated
- Carbamazepine + Elbasvir / grazoprevir Contraindicated
Other interactions of Lamotrigine
Frequently asked questions
Can I take Carbamazepine with Lamotrigine?
MediHelp rates the interaction as moderate. Carbamazepine and Lamotrigine 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. Carbamazepine lowers lamotrigine concentrations and may reduce seizure control. Neurotoxicity with diplopia, dizziness and ataxia is also reported, possibly from a pharmacodynamic effect.
How serious is the interaction between Carbamazepine and Lamotrigine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lamotrigine dosing schedule for patients on enzyme inducers and monitor for neurotoxicity. Reduce the lamotrigine dose if carbamazepine is withdrawn.
What other medicines interact with Carbamazepine?
MediHelp also lists interactions of Carbamazepine with, for example, Artemether / lumefantrine, Cabotegravir, Delamanid. The full list is on the Carbamazepine page.
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