Generic
Lamotrigine
17 brands available in the market
At a glance
Lamotrigine is an antiepileptic medicine used for epilepsy and bipolar disorder. It reduces abnormal nerve cell activity in the brain to control seizures and prevent extreme mood swings.
Description
Lamotrigine is a phenyltriazine antiepileptic that stabilizes neuronal membranes by inhibiting voltage-sensitive sodium channels and modulates the release of presynaptic excitatory neurotransmitters (glutamate and aspartate). It selectively binds to inactive sodium channels, inhibiting sodium currents and suppressing glutamate release. Lamotrigine displays weak binding to various receptors and inhibits some calcium currents, which may contribute to its anticonvulsant effects.
Indications
- Epilepsy - partial-onset seizures, primary generalized tonic-clonic seizures, Lennox-Gastaut syndrome (adjunctive therapy - 2 years+, monotherapy - 16 years+)
- Bipolar disorder - patients 18 years and older
Therapeutic class
Primary Anti-epileptic
Pharmacological class
Voltage-gated Sodium Channel Blocker
Pharmacology
Lamotrigine stabilizes neuronal membranes by inhibiting voltage-sensitive sodium channels and modulates the release of excitatory amino acids (glutamate and aspartate).
Mechanism of action
Stabilizes neuronal membranes and inhibits pathological release of excitatory amino acids by blocking voltage-gated sodium channels.
Dosage
Adult (Epilepsy - Monotherapy): Initial 25 mg daily for 2 weeks, then 50 mg daily for 2 weeks, then increase by 50-100 mg every 1-2 weeks to maintenance 100-200 mg/day (max 500 mg/day)
Adult (Bipolar): Initial 25 mg daily for 2 weeks, then 50 mg daily for 2 weeks, then double weekly to maintenance 200 mg/day
With Valproate: Reduce dose
With Enzyme-inducing Drugs: Increase dose
Hepatic Impairment: Moderate: 50% reduction; Severe: 75% reduction
Administration
- Swallow tablet whole; do not chew, crush or break
- Can be taken with or without food
- Take at the same time each day
Missed dose
If you miss a dose, take it as soon as possible. If it's almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common Side Effects:
- Skin rash
- Headache
- Nausea
- Vomiting
- Dry mouth
- Insomnia
- Drowsiness
- Dizziness
- Back pain
- Abdominal pain
- Blurred vision
- Double vision
- Impaired coordination
Precautions & warnings
- Discontinue at the first sign of rash
- Monitor for blood dyscrasias
- Monitor for suicidal behavior and ideation
- Monitor for aseptic meningitis
- Avoid driving or activities requiring concentration (may cause dizziness and double vision)
- Do not stop suddenly (may increase seizure frequency)
Contraindications
- Hypersensitivity to Lamotrigine or its components
Drug interactions
- Valproate decreases metabolism
- Enzyme-inducing drugs (phenytoin, carbamazepine) increase metabolism
- Estrogen-containing OCs decrease lamotrigine levels (~50%)
- Protease inhibitors decrease lamotrigine levels
Food interactions
Lamotrigine may cause excessive drowsiness with alcohol.
Use in pregnancy
Use in Pregnancy: May be unsafe during pregnancy (FDA Category C). Animal studies have shown harmful effects on the fetus. Consult your doctor.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Probably safe during breastfeeding. Limited human data suggests no significant risk to the baby. Monitor the baby for rash, sleepiness, or poor sucking.
Pediatric use
Epilepsy: 2 years+; Bipolar: 18 years+; Safety not established in patients aged 1-24 months.
Geriatric use
Start at the lower end of the dosing range in elderly.
Renal / hepatic impairment
Renal Impairment: Use with caution; consider dose reduction in significant renal impairment.
Hepatic Impairment: Moderate: 50% reduction; Severe: 75% reduction.
Overdose effects
Overdose may result in ataxia, nystagmus, seizures, decreased consciousness, coma, and intraventricular conduction delay.
Storage conditions
Store below 25°C in a dry place, protected from light; keep out of reach of children.
Chemical structure
Lamotrigine