Lacosamide G.L.
Antiepileptic medication for focal (partial-onset) seizures
Lacosamide G.L. is a prescription antiepileptic drug (AED) containing lacosamide as its active ingredient. It is indicated for the treatment of focal (partial-onset) seizures with or without secondary generalization in adults and adolescents aged 16 years and older. Lacosamide works through a unique mechanism that selectively enhances slow inactivation of voltage-gated sodium channels, distinguishing it from older sodium channel blockers. This guide covers dosage, side effects, drug interactions, and important safety information based on EMA, FDA, and ILAE guidelines.
Quick Facts
Key Takeaways
- Lacosamide G.L. is a generic antiepileptic drug bioequivalent to Vimpat, used for focal (partial-onset) seizures in adults and adolescents aged 16 and older.
- It works through a unique mechanism — selective enhancement of slow inactivation of voltage-gated sodium channels — which reduces neuronal hyperexcitability.
- The usual maintenance dose is 200–400 mg per day divided into two doses, with gradual titration starting at 50 mg twice daily.
- Common side effects include dizziness, headache, nausea, and double vision, which typically improve during the first weeks of treatment.
- Never stop lacosamide abruptly — gradual dose reduction over at least one week is essential to prevent increased seizure activity.
What Is Lacosamide G.L. and What Is It Used For?
Lacosamide G.L. belongs to the group of antiepileptic drugs (AEDs) and contains the active substance lacosamide. It is a generic version of the original branded product Vimpat, manufactured by G.L. Pharma. As a generic medication, it has been demonstrated to be bioequivalent to the original product, meaning it delivers the same amount of active ingredient to the body at the same rate and extent.
Epilepsy is a chronic neurological disorder characterized by recurrent, unprovoked seizures caused by abnormal electrical activity in the brain. Focal seizures, also known as partial-onset seizures, originate in a specific area of one hemisphere of the brain. These seizures may remain localized (simple focal seizures) or spread to affect consciousness (complex focal seizures), and they may also spread to involve both hemispheres, resulting in what is known as secondary generalization or focal to bilateral tonic-clonic seizures.
Lacosamide is indicated for the treatment of focal seizures with or without secondary generalization. It was first approved by the European Medicines Agency (EMA) in 2008 and by the United States Food and Drug Administration (FDA) in the same year. Since then, it has become one of the most widely prescribed newer-generation antiepileptic drugs worldwide, with a well-established safety and efficacy profile supported by numerous randomized controlled trials and long-term extension studies.
The medication can be used in two distinct clinical scenarios. As monotherapy, it serves as the sole antiepileptic drug for patients newly diagnosed with epilepsy or those being converted from other treatments. As adjunctive (add-on) therapy, it is combined with one or more other antiepileptic drugs in patients whose seizures are not adequately controlled by existing medication alone. Clinical trials have demonstrated that lacosamide significantly reduces seizure frequency in both settings compared to placebo.
According to the International League Against Epilepsy (ILAE), lacosamide is classified as a Level A (established efficacy) medication for adjunctive treatment of focal seizures and has Level C evidence as initial monotherapy. The ILAE 2022 classification of antiepileptic drugs recognizes lacosamide as having a favorable tolerability profile compared to many older antiepileptic medications, with fewer drug interactions and a more predictable pharmacokinetic profile.
How Does Lacosamide Work?
Lacosamide has a unique mechanism of action that distinguishes it from older antiepileptic drugs. While traditional sodium channel blockers such as carbamazepine, phenytoin, and lamotrigine primarily affect the fast inactivation of voltage-gated sodium channels, lacosamide selectively enhances slow inactivation of these channels. This is a fundamentally different pharmacological target.
Voltage-gated sodium channels exist in three conformational states: resting (closed), open (conducting), and inactivated (non-conducting). Fast inactivation occurs within milliseconds after channel opening, while slow inactivation develops over seconds to minutes during sustained or repetitive neuronal depolarization. By enhancing slow inactivation, lacosamide preferentially reduces the excitability of neurons that are firing abnormally and repetitively — exactly the pathological activity seen during seizures — while having minimal effect on normal neuronal signaling.
In addition to its sodium channel effects, lacosamide has been shown to bind to collapsin response mediator protein 2 (CRMP-2), a protein involved in neuronal differentiation and axonal outgrowth. However, the clinical significance of this interaction for seizure control remains under investigation. The dual mechanism may contribute to lacosamide's efficacy in patients who have not responded adequately to other sodium channel blockers.
What Should You Know Before Taking Lacosamide G.L.?
Contraindications
Lacosamide G.L. must not be used in the following situations:
- Known hypersensitivity: Allergy to lacosamide or any of the excipients in the formulation. Serious hypersensitivity reactions including anaphylaxis and angioedema have been reported.
- Second- or third-degree atrioventricular (AV) block: Lacosamide can prolong the PR interval and should not be used in patients with known second- or third-degree AV block without a pacemaker.
Additionally, caution is advised in patients with first-degree AV block, sick sinus syndrome without a pacemaker, or other significant cardiac conduction abnormalities. An electrocardiogram (ECG) should be obtained before initiating treatment in patients with known cardiac disease or those taking concomitant medications that prolong the PR interval.
Warnings and Precautions
Several important warnings should be considered when using lacosamide:
Antiepileptic drugs, including lacosamide, have been associated with a small but statistically significant increased risk of suicidal thoughts and behavior. A meta-analysis by the FDA found that the overall risk was approximately 0.43% in patients taking AEDs compared to 0.24% in those taking placebo. Patients should be monitored for signs of depression, unusual changes in mood or behavior, and suicidal ideation, particularly during the first months of treatment or during dose adjustments.
Cardiac Effects: Lacosamide causes dose-dependent prolongation of the PR interval on electrocardiograms. In clinical trials, first-degree AV block was reported in approximately 0.4% of patients. Cases of second-degree and complete AV block have been reported in post-marketing surveillance. Patients with underlying cardiac conduction disorders, those taking medications that prolong the PR interval (such as beta-blockers, calcium channel blockers, or other sodium channel blockers), and patients with severe cardiac disease should be closely monitored.
Dizziness and Ataxia: Lacosamide may cause dizziness and ataxia, which can increase the risk of falls and accidental injuries, particularly in elderly patients. These effects are most commonly observed during dose titration and typically subside as the patient adjusts to the medication.
Multiorgan Hypersensitivity Reactions: Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), also known as multiorgan hypersensitivity, has been reported with lacosamide. DRESS typically presents with fever, rash, lymphadenopathy, and involvement of one or more organ systems (hepatitis, nephritis, hematological abnormalities, myocarditis). If DRESS is suspected, lacosamide should be discontinued immediately.
Withdrawal Seizures: As with all antiepileptic medications, lacosamide should not be discontinued abruptly. Sudden withdrawal can precipitate rebound seizures, increased seizure frequency, or status epilepticus. If discontinuation is necessary, the dose should be gradually reduced over a minimum of one week (recommended withdrawal rate: decrease by 200 mg/week).
Pregnancy and Breastfeeding
The use of lacosamide during pregnancy requires careful risk-benefit assessment. There is limited data from the use of lacosamide in pregnant women. Animal studies have shown reproductive toxicity at doses that produce plasma concentrations similar to or slightly higher than therapeutic levels in humans.
All antiepileptic drugs carry some risk of teratogenicity, particularly during the first trimester. However, uncontrolled seizures during pregnancy also pose significant risks to both the mother and fetus, including hypoxia, trauma, and potential fetal loss. Therefore, epilepsy treatment should generally not be discontinued during pregnancy without careful medical supervision. The European Medicines Agency recommends that women of childbearing potential should use effective contraception during treatment and discuss family planning with their healthcare provider.
Lacosamide is excreted in human breast milk. A decision must be made whether to discontinue breastfeeding or to discontinue the medication, taking into account the benefit of breastfeeding for the child and the benefit of therapy for the woman. The amount of lacosamide transferred through breast milk is estimated to be relatively low, but the effects on the nursing infant have not been fully studied.
If you are pregnant, planning to become pregnant, or breastfeeding, discuss the risks and benefits of lacosamide with your neurologist before making any changes to your epilepsy treatment. Enrolling in a pregnancy registry (such as the International Registry of Antiepileptic Drugs and Pregnancy, EURAP) can help gather important safety data for future patients.
How Does Lacosamide G.L. Interact with Other Drugs?
One of the clinical advantages of lacosamide compared to older antiepileptic drugs such as carbamazepine, phenytoin, and phenobarbital is its relatively favorable drug interaction profile. Lacosamide does not significantly induce or inhibit cytochrome P450 enzymes, meaning it is less likely to alter the plasma levels of other medications. However, several important interactions should be considered.
Lacosamide is partially metabolized by the CYP2C19 enzyme system. Strong inducers of CYP2C19 and CYP3A4, such as rifampicin or St. John's wort, may reduce the plasma concentration of lacosamide by approximately 25%, potentially reducing its effectiveness. Conversely, strong CYP2C19 inhibitors such as fluconazole may increase lacosamide exposure, though this is generally not considered clinically significant in patients with normal renal function.
Major Interactions
| Drug / Class | Effect | Clinical Recommendation |
|---|---|---|
| PR interval-prolonging drugs (beta-blockers, calcium channel blockers, digoxin) | Additive PR prolongation; increased risk of AV block and bradycardia | ECG monitoring recommended; caution advised |
| Carbamazepine | CYP3A4 induction may reduce lacosamide levels; both drugs block sodium channels, increasing risk of CNS side effects | Monitor for dizziness, diplopia; dose adjustment may be needed |
| Phenytoin | CYP3A4 induction may reduce lacosamide levels; additive sodium channel blockade | Monitor therapeutic response; consider dose increase of lacosamide |
| Phenobarbital / Primidone | Strong enzyme induction may reduce lacosamide plasma concentration by up to 25% | Higher lacosamide doses may be required |
| Class I antiarrhythmics (flecainide, propafenone) | Additive cardiac conduction effects; increased risk of arrhythmias | Combination generally not recommended; ECG monitoring essential |
Minor Interactions
| Drug / Class | Effect | Clinical Recommendation |
|---|---|---|
| Levetiracetam, lamotrigine, topiramate | No clinically significant pharmacokinetic interaction | No dose adjustment needed; safe to combine |
| Valproate | No significant pharmacokinetic interaction | No dose adjustment needed |
| Oral contraceptives (ethinyl estradiol, levonorgestrel) | No effect on contraceptive hormone levels | No dose adjustment needed; contraceptive efficacy maintained |
| Metformin | No clinically relevant interaction | No dose adjustment needed |
| Omeprazole | CYP2C19 inhibition; minor increase in lacosamide exposure | Generally not clinically significant; no adjustment needed |
Patients should exercise caution when consuming alcohol during lacosamide treatment. Alcohol may enhance the CNS depressant effects of lacosamide, particularly dizziness and drowsiness, and may lower the seizure threshold. While occasional small amounts of alcohol may be acceptable for some patients, this should be discussed with your treating physician on an individual basis.
What Is the Correct Dosage of Lacosamide G.L.?
Lacosamide G.L. is administered orally as film-coated tablets. The tablets should be swallowed whole with water and can be taken with or without food, as food does not significantly affect the rate or extent of absorption. Lacosamide has a bioavailability of approximately 100% after oral administration, and peak plasma concentrations are reached within 1 to 4 hours. The elimination half-life is approximately 13 hours, supporting twice-daily dosing.
Adults
Adult Dosage (16 years and older)
| Phase | Dose | Duration |
|---|---|---|
| Starting dose | 50 mg twice daily (100 mg/day) | Week 1 |
| First increase | 100 mg twice daily (200 mg/day) | Week 2 |
| Second increase (if needed) | 150 mg twice daily (300 mg/day) | Week 3 |
| Maximum dose (if needed) | 200 mg twice daily (400 mg/day) | Week 4 onward |
| Maintenance dose range | 100–200 mg twice daily (200–400 mg/day) | Long-term |
The dose should be individually optimized based on seizure control and tolerability. Most patients achieve adequate seizure control at 200–400 mg/day. The dose should be increased in weekly increments of 50 mg twice daily (100 mg/day) to allow the body to adjust and minimize side effects.
Children and Adolescents
Lacosamide G.L. 50 mg tablets are approved for use in adolescents aged 16 years and older, with the same dosing recommendations as adults. For younger children (aged 4 years to less than 16 years), lacosamide is available in other formulations (oral solution) at weight-based doses, but the 50 mg tablet formulation described here is primarily intended for adolescents and adults.
For adolescents weighing more than 50 kg, the adult dosing schedule applies. For those under 50 kg who can swallow tablets, the starting dose may need to be lower and should be determined by the treating physician based on body weight. Clinical trials in pediatric populations have demonstrated similar efficacy and safety profiles to those observed in adults.
Elderly Patients
No dose adjustment is required for elderly patients based on age alone. However, age-related decreases in renal function should be considered, and the dose should be adjusted if creatinine clearance is reduced. Elderly patients may be more susceptible to CNS adverse effects such as dizziness and falls, so slower titration may be appropriate. The maximum recommended dose for elderly patients remains 400 mg/day.
Renal impairment: No dose adjustment is needed for patients with mild to moderate renal impairment (creatinine clearance >30 mL/min). In patients with severe renal impairment (creatinine clearance ≤30 mL/min) or end-stage renal disease, the maximum recommended dose is 300 mg/day. Lacosamide is removed by hemodialysis; a supplementary dose of up to 50% may be needed after a 4-hour dialysis session.
Hepatic impairment: Caution is advised in patients with moderate hepatic impairment (Child-Pugh B), and the maximum recommended dose should not exceed 300 mg/day. Lacosamide is not recommended in patients with severe hepatic impairment (Child-Pugh C) due to insufficient data.
Missed Dose
If you miss a dose of lacosamide, take it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a forgotten dose. If you are unsure about what to do, contact your pharmacist or doctor for advice.
Consistency in taking lacosamide is important for maintaining stable blood levels and optimal seizure control. Setting alarms or using a pill organizer can help ensure doses are not missed. If doses are frequently missed, discuss strategies with your healthcare provider.
Overdose
In case of suspected overdose, seek immediate medical attention or contact your local poison control center. Symptoms of lacosamide overdose may include nausea, vomiting, dizziness, seizures, cardiac conduction disturbances (including AV block and cardiac arrest), and decreased level of consciousness including coma. There is no specific antidote for lacosamide overdose. Treatment is supportive and may include hemodialysis, which effectively removes lacosamide from the blood (approximately 50% is removed during a 4-hour session).
What Are the Side Effects of Lacosamide G.L.?
Like all medications, lacosamide can cause side effects, although not everyone will experience them. The side effects listed below are based on data from randomized controlled clinical trials involving thousands of patients and post-marketing surveillance reports. Many of the common side effects are dose-dependent and are more likely to occur during the initial titration phase or when doses are increased rapidly.
Very Common
- Dizziness (up to 31% in clinical trials at higher doses)
- Headache
- Diplopia (double vision)
- Nausea
Common
- Drowsiness / somnolence
- Blurred vision
- Balance disorder / ataxia
- Tremor
- Nystagmus (involuntary eye movements)
- Memory impairment
- Cognitive disorder / difficulty concentrating
- Vomiting
- Constipation
- Flatulence
- Pruritus (itching)
- Fatigue
- Gait disturbance
- Falls
- Depression
Uncommon
- First-degree AV block
- Palpitations
- Tinnitus (ringing in the ears)
- Vertigo
- Elevated liver enzymes
- Rash
- Muscle spasms
- Abnormal coordination
Rare
- Second-degree or third-degree AV block
- Bradycardia
- Atrial fibrillation / flutter
- Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)
- Stevens-Johnson syndrome
- Toxic epidermal necrolysis
- Anaphylaxis / angioedema
- Agranulocytosis
- Suicidal ideation
The majority of adverse effects are CNS-related (dizziness, diplopia, drowsiness) and are most prominent during the titration phase. In clinical trials, the discontinuation rate due to adverse events was approximately 8–17% depending on the dose, compared to 5% for placebo. Slow dose titration helps minimize the incidence and severity of these effects.
Contact your doctor or go to the emergency department immediately if you experience: severe skin rash with fever and swollen lymph nodes (possible DRESS), chest pain or very slow or irregular heartbeat, severe allergic reactions (swelling of face, lips, tongue, or throat, difficulty breathing), or new or worsening depression or suicidal thoughts.
Long-term studies of lacosamide extending over several years have shown a stable safety profile, with no evidence of cumulative toxicity or new safety signals emerging with prolonged use. Weight neutrality is a notable advantage, as lacosamide does not typically cause significant weight gain or loss, unlike some other antiepileptic drugs such as valproate or topiramate.
How Should You Store Lacosamide G.L.?
Proper storage of medication is essential to ensure its effectiveness and safety throughout the shelf life. Lacosamide G.L. film-coated tablets should be stored in their original blister packaging or bottle until use, as this provides protection from light and moisture exposure that could degrade the active ingredient.
Store the tablets at room temperature, not exceeding 30°C (86°F). Do not store in the bathroom, near a sink, or in other damp places, as humidity can affect tablet integrity. Do not freeze the medication. Keep the container tightly closed when not in use.
All medications should be kept out of the sight and reach of children. Consider using a locked medicine cabinet if children are present in the household. Do not use Lacosamide G.L. after the expiry date printed on the packaging. The expiry date refers to the last day of that month.
Do not dispose of medicines via wastewater or household waste. Ask your pharmacist about how to dispose of medications you no longer use. Proper disposal helps protect the environment and prevents accidental ingestion by others. Many pharmacies offer medication take-back programs for safe disposal of unused or expired drugs.
What Does Lacosamide G.L. Contain?
The active substance in Lacosamide G.L. is lacosamide. Each film-coated tablet contains 50 mg of lacosamide. Lacosamide (chemical name: (R)-2-acetamido-N-benzyl-3-methoxypropionamide) is a functionalized amino acid that was first synthesized in the 1990s. Its molecular formula is C13H18N2O3, with a molecular weight of 250.30 g/mol.
The inactive ingredients (excipients) in the tablet core typically include microcrystalline cellulose, hydroxypropyl cellulose, crospovidone, magnesium stearate, and colloidal silicon dioxide. These excipients serve various functions: microcrystalline cellulose acts as a filler and binder, crospovidone facilitates tablet disintegration, and magnesium stearate serves as a lubricant during the manufacturing process.
The film coating contains hypromellose, titanium dioxide (E171), macrogol, and may contain iron oxide pigments depending on the tablet strength for identification purposes. The film coating protects the tablet core, improves swallowability, and provides a smooth appearance. The coating may also help mask any unpleasant taste of the active ingredient.
Patients with known allergies to any of these excipients should inform their healthcare provider before starting treatment. Lacosamide G.L. tablets are gluten-free and do not contain lactose, making them suitable for patients with celiac disease or lactose intolerance.
Frequently Asked Questions About Lacosamide G.L.
Lacosamide G.L. is an antiepileptic medication used to treat focal (partial-onset) seizures with or without secondary generalization in adults and adolescents aged 16 years and older with epilepsy. It can be used as a standalone treatment (monotherapy) or in combination with other antiepileptic drugs (adjunctive therapy). The medication works by selectively enhancing slow inactivation of voltage-gated sodium channels in the brain, which helps stabilize overactive nerve cells and reduce seizure frequency.
Lacosamide has a unique mechanism of action compared to other antiepileptic drugs. While older sodium channel blockers like carbamazepine and phenytoin affect fast inactivation of sodium channels, lacosamide selectively targets slow inactivation. This means it stabilizes hyperexcitable neurons without broadly affecting normal neuronal function. Additionally, lacosamide has fewer drug interactions than many older AEDs, does not require routine blood level monitoring, has approximately 100% oral bioavailability, and does not significantly affect oral contraceptive efficacy.
Lacosamide may cause dizziness, blurred vision, and drowsiness, which can impair your ability to drive or operate machinery. Until you know how lacosamide affects you, you should avoid driving or operating dangerous machinery. This is particularly important during the initial titration period and following dose increases. It is also important to note that epilepsy itself may affect driving eligibility — driving regulations for people with epilepsy vary by country and region. Consult your doctor and check your local driving authority's rules about epilepsy and driving.
No. You should never stop taking lacosamide suddenly without medical supervision. Abrupt discontinuation of any antiepileptic drug can trigger rebound seizures, increased seizure frequency, or even status epilepticus, which is a life-threatening medical emergency involving prolonged or repeated seizures. If your doctor decides to discontinue lacosamide, the dose will be gradually reduced over at least one week (typically by 200 mg/week). Always discuss any desire to stop or change your medication with your neurologist first.
Lacosamide G.L. is a generic version of Vimpat, manufactured by G.L. Pharma. It contains the same active ingredient (lacosamide) at the same strength and has been proven to be bioequivalent to the original branded product. This means it is absorbed and distributed in the body in the same way and to the same extent. Generic medications must meet strict quality, safety, and efficacy standards set by regulatory authorities such as the European Medicines Agency (EMA). The primary difference is the manufacturer and potentially the inactive ingredients (excipients), though these are pharmacologically inert.
Lacosamide is generally considered weight-neutral, meaning it does not typically cause significant weight gain or weight loss. This is an important advantage compared to some other antiepileptic drugs. For example, valproate and pregabalin are associated with weight gain, while topiramate and zonisamide may cause weight loss. In clinical trials of lacosamide, changes in body weight were minimal and not statistically different from placebo. However, individual responses may vary, and any unexpected weight changes should be discussed with your doctor.
References
This article is based on the following peer-reviewed sources and international medical guidelines:
- European Medicines Agency (EMA). Vimpat (lacosamide) – Summary of Product Characteristics. Last updated 2025.
- U.S. Food and Drug Administration (FDA). VIMPAT (lacosamide) Prescribing Information. UCB, Inc. Revised 2024.
- Halász P, Kälviäinen R, Mazurkiewicz-Beldzinska M, et al. Adjunctive lacosamide for partial-onset seizures: Efficacy and safety results from a randomized controlled trial. Epilepsia. 2009;50(3):443-453.
- Ben-Menachem E, Biton V, Jatuzis D, et al. Efficacy and safety of oral lacosamide as adjunctive therapy in adults with partial-onset seizures. Epilepsia. 2007;48(7):1308-1317.
- Wechsler RT, Li G, French J, et al. Conversion to lacosamide monotherapy in the treatment of focal epilepsy: Results from a historical-controlled, multicenter, double-blind study. Epilepsia. 2014;55(7):1088-1098.
- Sake JK, Hebert D, Isojärvi J, et al. A pooled analysis of lacosamide clinical trial data grouped by mechanism of action of concomitant antiepileptic drugs. CNS Drugs. 2010;24(12):1055-1068.
- International League Against Epilepsy (ILAE). Report of the ILAE Commission on Classification and Terminology. 2022 Update.
- Perucca E, Brodie MJ, Kwan P, Tomson T. 30 years of second-generation antiseizure medications: impact and future perspectives. Lancet Neurol. 2023;22(6):544-556.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List. 2023.
- British National Formulary (BNF). Lacosamide Drug Monograph. National Institute for Health and Care Excellence (NICE). Updated 2025.
Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, comprising licensed specialist physicians with expertise in neurology, epilepsy, and clinical pharmacology.
iMedic Editorial Team — specialists in clinical pharmacology and neurology with extensive experience in evidence-based medical communication.
iMedic Medical Review Board — independent panel of board-certified neurologists and clinical pharmacologists who review all content according to EMA, FDA, and ILAE guidelines.
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