Last reviewed 2026-04-22 · How we verify

Lamotrigine generic "B"

Lamotrigine blocks voltage-gated sodium channels and inhibits glutamate release, reducing neuronal excitability.

Lamotrigine blocks voltage-gated sodium channels and inhibits glutamate release, reducing neuronal excitability. Used for Epilepsy (adjunctive therapy for partial seizures), Bipolar I disorder (maintenance treatment to delay time to occurrence of mood episodes).

At a glance

Mechanism of action

Lamotrigine stabilizes neuronal membranes by blocking sodium channels, which prevents repetitive neuronal firing. It also inhibits the release of glutamate, an excitatory neurotransmitter, thereby reducing excessive neuronal activity. These combined effects make it effective as an anticonvulsant and mood stabilizer.

Approved indications

• Epilepsy (adjunctive therapy for partial seizures)
• Bipolar I disorder (maintenance treatment to delay time to occurrence of mood episodes)

Common side effects

• Rash (including Stevens-Johnson syndrome risk)
• Dizziness
• Ataxia
• Somnolence
• Headache
• Diplopia
• Nausea

Key clinical trials

• Equivalence Among Antiepileptic Drug Generic and Brand Products in People With Epilepsy: Single-Dose 6-Period Replicate Design (EQUIGEN Single-Dose Study) (PHASE4)
• Equivalence Among Antiepileptic Drug Generic and Brand Products in People With Epilepsy: Chronic-Dose 4-Period Replicate Design (PHASE4)

Primary sources

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