Lamotrigine

Pronunciation: la-MOE-tri-jeen.

Generic name
lamotrigine
Drug class
Antiepileptic drug (AED) -- sodium channel blocker
Form
Tablets, dispersible/chewable tablets, orally disintegrating tablets (ODT)
Route
Oral
Legal status
Prescription-only

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: Lamictal (5) · Full directory

What lamotrigine is and how it works

Lamotrigine is a prescription-only antiepileptic medicine used to help control certain types of seizures and, separately, to help delay mood episodes in people with bipolar I disorder who are already stable on treatment. (1)

Take lamotrigine exactly as your prescriber directs. Your prescriber will start you on a low dose and increase it slowly over several weeks -- this careful, gradual increase is a genuine safety measure, not just a formality, because starting too high or increasing too fast raises the risk of a serious rash.

Mechanism of action: how lamotrigine works

Lamotrigine blocks voltage-sensitive sodium channels, stabilising neuronal membranes and inhibiting the release of excitatory neurotransmitters such as glutamate. (1)

What lamotrigine is used for

Epilepsy

Used with other antiepileptic medicines (adjunctive therapy), or alone in some adults and adolescents switching from a single other antiepileptic medicine, to help control partial seizures, primary generalised tonic-clonic seizures, and the generalised seizures of Lennox-Gastaut syndrome. (1)

Bipolar I disorder (maintenance)

Used in adults to help delay the return of mood episodes (depression, mania, or mixed episodes) after a mood episode has already been treated with standard therapy. It is not established as a treatment for a mood episode that is happening right now. (1)

Before taking lamotrigine

Do not take / not appropriate for

  • Do not take lamotrigine if you have had a serious allergic reaction to it or any of its ingredients. (all countries) (1)

Tell your clinician about

  • Whether you take, or are stopping, sodium valproate or any other antiepileptic medicine -- this changes how your titration schedule and dose need to be planned.
  • Any personal or family history of low mood, self-harm, or suicidal thoughts.
  • Any history of meningitis symptoms or unexplained rash with a previous antiepileptic medicine.
  • Any kidney or liver problems.
  • Pregnancy, plans for pregnancy, or breastfeeding -- ask about the Lamotrigine Pregnancy Registry.
  • All other medicines you take, including hormonal contraceptives, which can affect lamotrigine levels.
(1)

How to take lamotrigine

  • Take lamotrigine exactly as prescribed, at the times your prescriber sets.
  • Follow your prescriber's titration schedule precisely -- do not increase your own dose faster than instructed, even if you feel your seizures or mood are not fully controlled yet; ask your prescriber first.
  • Continue taking lamotrigine for as long as your prescriber recommends, even if you feel well.
  • If you and your prescriber ever decide together to stop or change this medicine, your prescriber will taper the dose down gradually, usually over at least 2 weeks, rather than stopping it suddenly -- to reduce the risk of a rebound increase in seizures.
(1)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (3) (2) (4) (5) (6)

Missed dose

If you miss a dose, contact your prescriber or pharmacist for guidance specific to your titration schedule, since taking a missed dose late or skipping it can affect your levels differently depending on where you are in the titration process. Do not take two doses together to make up for a missed one without checking first.

Overdose

Seek emergency medical help immediately if you think too much lamotrigine has been taken, or if severe drowsiness, loss of coordination, irregular heartbeat, or seizures occur. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Dizziness, loss of coordination (ataxia), and drowsiness.

What to notice: Dizziness, loss of coordination (ataxia), and drowsiness.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Headache.

What to notice: Headache.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Double or blurred vision.

What to notice: Double or blurred vision.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Nausea and vomiting.

What to notice: Nausea and vomiting.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Mild rash (any rash still needs prompt clinician assessment -- see the warning above).

What to notice: Mild rash (any rash still needs prompt clinician assessment -- see the warning above).

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Serious warnings

Signs of a serious skin rash (Stevens-Johnson syndrome or toxic epidermal necrolysis) — boxed_warning

Symptoms: A new or spreading rash, especially with blistering or peeling skin, painful mouth or eye sores, fever, or swollen glands -- most often appearing within the first 2 to 8 weeks of treatment.

Action: Get medical help the same day at the first sign of any rash, even a mild one -- your prescriber needs to assess it urgently, since lamotrigine is ordinarily stopped promptly on their advice unless the rash is clearly unrelated to the medicine. Never wait to see whether it improves on its own. (1)

Multiorgan hypersensitivity reaction (DRESS) — emergency

Symptoms: Fever, rash, and swollen glands together with signs of other organ involvement, such as yellowing of the skin or eyes, unusual bruising, or severe fatigue.

Action: Seek emergency medical help immediately -- DRESS can be fatal and needs urgent evaluation. (1)

Signs of aseptic meningitis — emergency

Symptoms: Headache, fever, nausea, vomiting, a stiff neck, and sometimes rash, sensitivity to light, or confusion -- reported from within a day up to about 6 weeks after starting treatment.

Action: Seek emergency medical help immediately for these symptoms. (1)

Signs of a blood disorder — high caution

Symptoms: Unusual bruising or bleeding, persistent sore throat or fever, or unusual tiredness or paleness.

Action: Contact your prescriber promptly for blood tests -- rare blood disorders have been reported with lamotrigine. (1)

New or worsening mood or behaviour changes, including suicidal thoughts — high caution

Symptoms: New or worsening depression, anxiety, agitation, irritability, or thoughts of self-harm or suicide.

Action: Tell your prescriber promptly about any mood or behaviour changes -- as a class, antiepileptic medicines carry an increased risk of suicidal thinking or behaviour, and monitoring by your care team is part of safe treatment. (1)

Increased seizures after a change or gap in treatment — high caution

Symptoms: Seizures returning or becoming more frequent than usual.

Action: Never change your dose or leave gaps in your lamotrigine treatment without your prescriber's guidance -- any planned change should always be tapered gradually by your prescriber, usually over at least 2 weeks, to reduce the risk of a rebound increase in seizures. (1)

Interactions

  • Sodium valproate more than doubles lamotrigine levels in the body, so your prescriber will use a lower starting dose, slower titration, and lower maintenance dose if you take both. (1)
  • Carbamazepine, phenytoin, phenobarbital, and primidone reduce lamotrigine levels by about 40%, so your prescriber will usually plan for a higher maintenance dose. (1)
  • Oestrogen-containing hormonal contraceptives and rifampin can reduce lamotrigine levels by about 50% -- your prescriber may need to adjust your dose, including when you start or stop hormonal contraception. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Ask your prescriber about enrolling in the Lamotrigine Pregnancy Registry or the North American Antiepileptic Drug Pregnancy Registry, which track outcomes in pregnancy. Seizure control during pregnancy is important, and treatment decisions should be made with your prescriber. (1) (3) (2) (4) (5) (6)

Breastfeeding

Lamotrigine passes into breast milk. Discuss the benefits and risks with your prescriber before breastfeeding. (1) (3) (2) (4) (5) (6)

Children

Approved for epilepsy from age 2 in adjunctive use in some countries; not approved for bipolar disorder in children. Age thresholds vary by indication and country. (1) (3) (2) (4) (5) (6)

Elderly

No specific dose adjustment based on age alone is described in the source reviewed, but dosing is always individualised. (1) (3) (2) (4) (5) (6)

Hepatic_impairment

Liver problems can change how lamotrigine is cleared from the body -- tell your prescriber about any liver issues so your dose can be adjusted. (1) (3) (2) (4) (5) (6)

Renal_impairment

Kidney problems can affect lamotrigine clearance -- tell your prescriber about any kidney issues. (1) (3) (2) (4) (5) (6)

Monitoring

Before starting

  • Review of all current antiepileptic and hormonal medicines (for valproate/enzyme-inducer/contraceptive interactions)
  • Baseline mood and mental health screening
  • Discussion of the rash warning and titration schedule

During treatment

  • Close monitoring for any new rash, especially in the first 2 to 8 weeks.
  • Monitoring for mood or behaviour changes.
  • Periodic review of seizure control or mood-episode frequency.
  • Blood tests if any signs of a blood disorder appear.
(1)

Storage

Store at controlled room temperature as directed on the pack, protected from moisture. Keep out of reach of children.

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information; verify against the current full label before prescribing.

United States

Indication: Epilepsy (adjunctive/monotherapy) and bipolar I disorder maintenance

Dose summary: Individualised titration over 5-6 weeks; with valproate, lower starting dose and target maintenance (approx. 100-200 mg/day); with enzyme-inducing AEDs (carbamazepine, phenytoin, phenobarbital, primidone) and no valproate, higher target maintenance (approx. 300-500 mg/day); without either, target maintenance approx. 225-375 mg/day (epilepsy, adjunctive, adult). LAMICTAL Starter Kits match the recommended titration schedule for the first 5 weeks.

Renal context: Not established in detail in the source reviewed for this dossier; renal impairment can alter lamotrigine clearance and should prompt closer monitoring and dose adjustment. (1)

Mechanism of action

Hepatic guidance

Hepatic impairment can alter lamotrigine clearance; dose adjustment and closer monitoring are recommended.

Overdose note

Overdose can cause severe drowsiness, ataxia, nystagmus, intraventricular conduction delay, coma, and, in severe cases, seizures; management is supportive with close cardiac and neurological monitoring. (1)

Frequently asked questions

Is lamotrigine (Lamictal) available in the US, UK, Europe, Canada, Australia, and New Zealand?

Yes, it is approved and available in all of these regions. (1) (3) (2) (4) (5) (6)

Why do I have to increase my lamotrigine dose so slowly?

Starting too high or increasing the dose too quickly is a known, real risk factor for the serious skin rashes lamotrigine can cause. Following your prescriber's exact titration schedule -- never a faster one you choose yourself -- is an important safety measure. (1)

Can I just stop taking lamotrigine if I feel fine?

No -- stopping lamotrigine abruptly can increase the risk of seizures returning or worsening. If you and your prescriber decide together that treatment should stop, your prescriber will taper the dose down gradually. (1)

What is the mechanism of action of lamotrigine?

Lamotrigine blocks voltage-sensitive sodium channels, stabilising neuronal membranes and inhibiting the release of excitatory neurotransmitters such as glutamate. (1)

What is the generic name of Lamotrigine?

The generic name is lamotrigine. (1)

What class of drug is lamotrigine?

Lamotrigine is classed as: Antiepileptic drug (AED) -- sodium channel blocker. (1)

References

  1. LAMICTAL (lamotrigine) tablets, tablets for oral suspension, ODT -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, GlaxoSmithKline · United States · accessed 2026-07-29 · source 1
  2. Lamictal Tablets -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- GlaxoSmithKline · United Kingdom · accessed 2026-07-29 · source 2
  3. Lamictal and associated names, INN-lamotrigine -- Article 30 referral / EMA medicines pageEuropean Medicines Agency (EMA) · European Union · accessed 2026-07-29 · source 3
  4. Lamotrigine Tablets -- Product MonographHealth Canada product monograph · Canada · accessed 2026-07-29 · source 4
  5. LAMICTAL lamotrigine 200 mg dispersible/chewable tablet blister pack -- ARTG registrationTherapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-29 · source 5
  6. Lamictal (lamotrigine) dispersible/chewable tablets -- New Zealand Data SheetMedsafe (New Zealand regulator) · New Zealand · accessed 2026-07-29 · source 6

Brand names by country

Single-ingredient lamotrigine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • LAMICTAL300 mg, 250 mg, 200 mg, 5 mg, 100 mg, 25 mg, 150 mg, 50 mg · glaxosmithkline llc
  • SUBVENITE10 mg/mL, 150 mg, 100 mg, 25 mg, 200 mg · owp pharmaceuticals, inc.

United Kingdom

  • Lamictal (2)MHRA licensed emc smpc confirmed · 25 mg, 50 mg, 100 mg, 200 mg · GlaxoSmithKline UK

Canada

  • LAMICTAL

Australia

  • Lamictal (5)TGA ARTG registered 1997-06-10 confirmed · 200 mg (this entry) · Aspen Pharmacare Australia Pty Ltd

New Zealand

  • Lamictal (6)Medsafe approved confirmed · not specified in fetched source · not specified in fetched source
View brands in additional countries.

European Union

Lamictal (3)

This page provides general reference information about lamotrigine and is not a substitute for advice from the prescriber managing your treatment. All dosing and treatment decisions should be made with your prescriber.

Related medicines

Related conditions