Lamotrigine ER 50mg Tablets
WARNING: Severe skin reactions may happen with this drug. These include Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and other serious reactions. Sometimes, body organs may also be affected. These reactions can be deadly. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin; red or irritated eyes; sores in your mouth, throat, nose, eyes, genitals, or any areas of skin; fever; chills; body aches; shortness of breath; or swollen glands. The chance of a skin reaction is raised in children between 2 and 17 years old. It may also be raised if you take valproic acid or divalproex sodium with this drug, if you start taking this drug at too high of a dose, or if your dose is raised too fast. Skin reactions have also happened without any of these. Talk with your doctor.Most cases of skin reactions have happened within 2 to 8 weeks of starting this drug, but some show up after longer treatment like 6 months. Talk with the doctor.This drug is not approved for use in children younger than 13 years old. Talk with the doctor. @ COMMON USES: It is used to help control certain kinds of seizures.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Anticonvulsant
Pharmacologic Class
Phenyltriazine derivative; Voltage-gated sodium channel blocker
Pregnancy Category
Category C
FDA Approved
Jul 2009
DEA Schedule
Not Controlled
Overview
What is this medicine?
Lamotrigine ER is an extended-release medication used to treat certain types of seizures (epilepsy) and to help stabilize mood in people with bipolar disorder. It works by calming overactive nerve signals in the brain. The extended-release form means you take it once a day, and it releases the medicine slowly over time.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided to you and follow the instructions precisely. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
It's essential to swallow the medication whole, without chewing, breaking, or crushing it. If you have difficulty swallowing, consult your doctor for guidance. Do not alter the dose or stop taking this medication without consulting your doctor, as this may lead to seizures. If you need to stop taking this medication, your doctor will advise you on how to gradually discontinue it to minimize the risk of side effects.
If you stop taking this medication and need to restart it, your doctor may recommend starting with a lower dose and gradually increasing it. Be sure to discuss this with your doctor.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided to you and follow the instructions precisely. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
It's essential to swallow the medication whole, without chewing, breaking, or crushing it. If you have difficulty swallowing, consult your doctor for guidance. Do not alter the dose or stop taking this medication without consulting your doctor, as this may lead to seizures. If you need to stop taking this medication, your doctor will advise you on how to gradually discontinue it to minimize the risk of side effects.
If you stop taking this medication and need to restart it, your doctor may recommend starting with a lower dose and gradually increasing it. Be sure to discuss this with your doctor.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses.
Lifestyle & Tips
- Take exactly as prescribed; do not crush, chew, or divide the extended-release tablets.
- Do not stop taking this medication suddenly, as it can lead to increased seizures or withdrawal symptoms. Any dose changes must be gradual and supervised by your doctor.
- Avoid activities requiring mental alertness, such as driving or operating machinery, until you know how this medication affects you, as it can cause dizziness or drowsiness.
- Report any new rash immediately to your doctor, as it could be a sign of a serious, life-threatening reaction.
- Inform your doctor about all other medications you are taking, including over-the-counter drugs, herbal supplements, and especially hormonal birth control, as they can affect lamotrigine levels.
- Carry a medical alert card or wear a medical alert bracelet indicating you are taking lamotrigine.
Available Forms & Alternatives
Available Strengths:
- Lamotrigine 150mg Tablets
- Lamotrigine 200mg Tablets
- Lamotrigine 25mg Tablets
- Lamotrigine 100mg Tablets
- Lamotrigine 25mg Chew/disprsbl Tab
- Lamotrigine 5mg Chew/disprsbl Tab
- Lamotrigine ER 50mg Tablets
- Lamotrigine ER 200mg Tablets
- Lamotrigine ER 100mg Tablets
- Lamotrigine 300mg ER Tablets
- Lamotrigine ER 25mg Tablets
- Lamotrigine ODT 25mg Tablets
- Lamotrigine ODT 50mg Tablets
- Lamotrigine Orge Strt Kit25/100mg
- Lamotrigine Blue Starter Kit 25mg T
- Lamotrigine Green Str Kit 25/100mg
- Lamotrigine ODT 100mg Tablets
- Lamotrigine ODT 200mg Tablets
- Lamotrigine ER 250mg Tablets
- Lamotrigine ODT 25-50-100mg Tb Kit
Dosing & Administration
Adult Dosing
Standard Dose:
Initial titration varies based on concomitant medications. For patients not taking enzyme-inducing AEDs or valproate, initial dose is typically 25 mg once daily for 2 weeks, then 50 mg once daily for 2 weeks, then 100 mg once daily for 1 week, then 150 mg once daily for 1 week, then 200 mg once daily. Maintenance dose is typically 300-400 mg once daily.
Dose Range:
100 - 600 mg
Condition-Specific Dosing:
epilepsy_monotherapy:
Initial: 25 mg once daily for 2 weeks, then 50 mg once daily for 2 weeks, then 100 mg once daily for 1 week, then 150 mg once daily for 1 week, then 200 mg once daily. Maintenance: 300-400 mg once daily.
epilepsy_adjunctive_with_valproate:
Initial: 25 mg every other day for 2 weeks, then 25 mg once daily for 2 weeks, then 50 mg once daily for 1 week, then 75 mg once daily for 1 week, then 100 mg once daily. Maintenance: 100-200 mg once daily.
epilepsy_adjunctive_with_enzyme_inducers_without_valproate:
Initial: 50 mg once daily for 2 weeks, then 100 mg once daily for 2 weeks, then 200 mg once daily for 1 week, then 300 mg once daily for 1 week, then 400 mg once daily. Maintenance: 400-600 mg once daily.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established for patients under 13 years of age for ER formulation.
Adolescent:
For partial-onset seizures (13 years and older): Dosing similar to adult recommendations, adjusted based on concomitant medications. Initial titration is crucial and slow.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment required.
Moderate:
No specific dose adjustment required, but caution advised.
Severe:
Consider a reduction in maintenance dose by 25% for patients with significant renal impairment (CrCl < 30 mL/min).
Dialysis:
Supplemental doses after dialysis are generally not required as only a small fraction is removed. Monitor clinical response.
Hepatic Impairment:
Mild:
No specific dose adjustment required.
Moderate:
Consider a 25% reduction in initial, escalation, and maintenance doses (Child-Pugh B).
Severe:
Consider a 50% reduction in initial, escalation, and maintenance doses (Child-Pugh C).
Pharmacology
Mechanism of Action
Lamotrigine is a phenyltriazine derivative that is thought to exert its anticonvulsant effects by inhibiting voltage-sensitive sodium channels, thereby stabilizing neuronal membranes and inhibiting the release of excitatory neurotransmitters (e.g., glutamate and aspartate). It also has weak effects on voltage-gated calcium channels and may modulate serotonin 5-HT3 receptors.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 98% (oral)
Tmax:
Approximately 4-6 hours (for ER formulation, can be up to 10-12 hours for peak plasma concentration)
FoodEffect:
Food does not significantly affect the extent of absorption, but may slightly delay Tmax.
Distribution:
Vd:
Approximately 0.9-1.3 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 25-33 hours (monotherapy); significantly reduced by enzyme-inducing AEDs (e.g., 13-14 hours) and prolonged by valproate (e.g., 59-70 hours).
Clearance:
Approximately 30 mL/min (monotherapy)
ExcretionRoute:
Renal (approximately 94% as metabolites, 2% unchanged)
Unchanged:
Approximately 2%
Pharmacodynamics
OnsetOfAction:
Gradual, due to slow titration schedule (weeks to months)
PeakEffect:
Achieved after reaching stable maintenance dose (weeks to months)
DurationOfAction:
Once daily dosing due to extended-release formulation and half-life.
Safety & Warnings
BLACK BOX WARNING
Serious Skin Rashes: Lamotrigine can cause serious rashes requiring hospitalization and discontinuation of treatment. These include Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS). The incidence of these rashes, which have resulted in death, is approximately 0.3% to 0.8% in pediatric patients (aged 2 to 16 years) and 0.08% to 0.3% in adults. Risk factors include concomitant use of valproate, exceeding recommended initial doses, and rapid dose escalation. Benign rashes also occur, but it is not possible to predict which rashes will prove to be serious or life-threatening. Therefore, lamotrigine should ordinarily be discontinued at the first sign of rash, unless the rash is clearly not drug-related.
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of liver problems, such as:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Shortness of breath
Sudden weight gain
Swelling in the arms or legs
Severe muscle pain or weakness
Severe joint pain or swelling
Changes in vision
Chest pain or pressure
Abnormal heartbeat (fast, slow, or irregular)
Severe dizziness or fainting
Balance problems
Uncontrolled eye movements
Flu-like symptoms
Painful menstrual periods
Changes in menstrual cycle, including spotting or bleeding between periods
Low Blood Cell Counts and Infections
This medication can cause low blood cell counts, which may increase the risk of bleeding, infections, or anemia. If you experience any of the following symptoms, contact your doctor right away:
Signs of infection, such as fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Immune System Problem: Hemophagocytic Lymphohistiocytosis (HLH)
In rare cases, this medication can cause a life-threatening immune system problem called HLH. If you experience any of the following symptoms, contact your doctor immediately:
Fever
Swollen glands
Rash
Seizures
Confusion or decreased alertness
Balance problems
Difficulty walking (new or worsening)
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects, contact your doctor if they bother you or do not go away:
Dizziness, drowsiness, fatigue, or weakness
Constipation, diarrhea, stomach pain, upset stomach, vomiting, or decreased appetite
Shakiness
Sleep disturbances
Nose or throat irritation
Weight loss
Dry mouth
* Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of liver problems, such as:
+ Dark urine
+ Fatigue
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Shortness of breath
Sudden weight gain
Swelling in the arms or legs
Severe muscle pain or weakness
Severe joint pain or swelling
Changes in vision
Chest pain or pressure
Abnormal heartbeat (fast, slow, or irregular)
Severe dizziness or fainting
Balance problems
Uncontrolled eye movements
Flu-like symptoms
Painful menstrual periods
Changes in menstrual cycle, including spotting or bleeding between periods
Low Blood Cell Counts and Infections
This medication can cause low blood cell counts, which may increase the risk of bleeding, infections, or anemia. If you experience any of the following symptoms, contact your doctor right away:
Signs of infection, such as fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Immune System Problem: Hemophagocytic Lymphohistiocytosis (HLH)
In rare cases, this medication can cause a life-threatening immune system problem called HLH. If you experience any of the following symptoms, contact your doctor immediately:
Fever
Swollen glands
Rash
Seizures
Confusion or decreased alertness
Balance problems
Difficulty walking (new or worsening)
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects, contact your doctor if they bother you or do not go away:
Dizziness, drowsiness, fatigue, or weakness
Constipation, diarrhea, stomach pain, upset stomach, vomiting, or decreased appetite
Shakiness
Sleep disturbances
Nose or throat irritation
Weight loss
Dry mouth
* Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Any new skin rash, especially if it spreads, blisters, or is accompanied by fever, swollen glands, or facial swelling.
- Signs of allergic reaction: hives, difficulty breathing, swelling of your face, lips, tongue, or throat.
- Signs of liver problems: nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
- Signs of blood problems: fever, chills, sore throat, swollen gums, mouth sores, pale skin, easy bruising or bleeding.
- Increased seizures or new types of seizures.
- Worsening depression, suicidal thoughts, or unusual changes in behavior or mood.
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, any of its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking dofetilide, as this may interact with the medication.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your medical history, including any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor to confirm it is safe to do so.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, any of its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking dofetilide, as this may interact with the medication.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your medical history, including any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor to confirm it is safe to do so.
Precautions & Cautions
Important Warnings and Cautions
When taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are using this drug.
Caution with Daily Activities
Avoid driving and engaging in activities that require alertness until you understand how this medication affects you. It may take several weeks to experience the full effects of the drug.
Monitoring and Lab Tests
Regular blood work is necessary, as directed by your doctor. Be sure to inform all your healthcare providers and laboratory personnel that you are taking this medication, as it may affect certain lab test results.
Interactions with Other Substances
Before consuming alcohol, marijuana, or other forms of cannabis, or taking prescription or over-the-counter (OTC) medications that may cause drowsiness, consult with your doctor.
Mental Health and Suicidal Thoughts
Like other seizure medications, this drug may rarely increase the risk of suicidal thoughts or actions, particularly in individuals with a history of suicidal ideation. Immediately contact your doctor if you experience new or worsening symptoms such as depression, anxiety, restlessness, irritability, panic attacks, or changes in mood or behavior. If you have suicidal thoughts or actions, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of a severe brain condition called aseptic meningitis. Seek medical attention immediately if you experience symptoms such as headache, fever, chills, severe nausea or vomiting, stiff neck, rash, sensitivity to light, drowsiness, or confusion.
Medication Verification
Always verify that you have the correct medication, as some drugs may have similar names or appearances. If you notice any changes in the medication's shape, color, size, or labeling, consult with your pharmacist.
Heart Problems
If you have a history of abnormal heartbeat, heart failure, or other heart problems, discuss this with your doctor, as these conditions may increase the risk of abnormal heartbeats, which can lead to sudden death.
Pediatric Use
When using this medication in children, exercise caution, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult with your doctor before starting or stopping any hormone-based birth control method. The risk of side effects may be increased during the week when birth control pills are not active. Additionally, birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an alternative form of birth control, such as a condom.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor.
Seizure Management
If your seizures change or worsen after starting this medication, consult with your doctor.
When taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are using this drug.
Caution with Daily Activities
Avoid driving and engaging in activities that require alertness until you understand how this medication affects you. It may take several weeks to experience the full effects of the drug.
Monitoring and Lab Tests
Regular blood work is necessary, as directed by your doctor. Be sure to inform all your healthcare providers and laboratory personnel that you are taking this medication, as it may affect certain lab test results.
Interactions with Other Substances
Before consuming alcohol, marijuana, or other forms of cannabis, or taking prescription or over-the-counter (OTC) medications that may cause drowsiness, consult with your doctor.
Mental Health and Suicidal Thoughts
Like other seizure medications, this drug may rarely increase the risk of suicidal thoughts or actions, particularly in individuals with a history of suicidal ideation. Immediately contact your doctor if you experience new or worsening symptoms such as depression, anxiety, restlessness, irritability, panic attacks, or changes in mood or behavior. If you have suicidal thoughts or actions, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of a severe brain condition called aseptic meningitis. Seek medical attention immediately if you experience symptoms such as headache, fever, chills, severe nausea or vomiting, stiff neck, rash, sensitivity to light, drowsiness, or confusion.
Medication Verification
Always verify that you have the correct medication, as some drugs may have similar names or appearances. If you notice any changes in the medication's shape, color, size, or labeling, consult with your pharmacist.
Heart Problems
If you have a history of abnormal heartbeat, heart failure, or other heart problems, discuss this with your doctor, as these conditions may increase the risk of abnormal heartbeats, which can lead to sudden death.
Pediatric Use
When using this medication in children, exercise caution, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult with your doctor before starting or stopping any hormone-based birth control method. The risk of side effects may be increased during the week when birth control pills are not active. Additionally, birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an alternative form of birth control, such as a condom.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor.
Seizure Management
If your seizures change or worsen after starting this medication, consult with your doctor.
Overdose Information
Overdose Symptoms:
- Ataxia (loss of coordination)
- Nystagmus (involuntary eye movements)
- Increased seizures
- Decreased consciousness
- Coma
What to Do:
Seek immediate medical attention or call Poison Control at 1-800-222-1222. There is no specific antidote; treatment is supportive.
Drug Interactions
Major Interactions
- Valproate (increases lamotrigine levels significantly, requiring dose reduction)
- Carbamazepine, Phenytoin, Phenobarbital, Primidone (decrease lamotrigine levels significantly, requiring dose increase)
- Estrogen-containing oral contraceptives (decrease lamotrigine levels, requiring dose increase)
- Rifampin (decreases lamotrigine levels)
- Lopinavir/Ritonavir (decreases lamotrigine levels)
- Atazanavir/Ritonavir (decreases lamotrigine levels)
Moderate Interactions
- Paracetamol (acetaminophen) (may slightly decrease lamotrigine levels with chronic high doses)
- Risperidone (lamotrigine may decrease risperidone levels)
- Olanzapine (lamotrigine may decrease olanzapine levels)
- Lithium (no significant pharmacokinetic interaction, but potential for additive CNS effects)
- Bupropion (may increase lamotrigine levels)
Minor Interactions
- Folic acid (may slightly decrease lamotrigine levels)
Monitoring
Baseline Monitoring
Complete Blood Count (CBC)
Rationale: To establish baseline and monitor for potential hematologic abnormalities (rare).
Timing: Prior to initiation
Liver Function Tests (LFTs)
Rationale: To establish baseline and monitor for potential hepatic impairment, especially in patients with pre-existing liver disease.
Timing: Prior to initiation
Renal Function Tests (Creatinine, BUN)
Rationale: To establish baseline and guide dose adjustments in severe renal impairment.
Timing: Prior to initiation
Skin assessment
Rationale: To document baseline skin condition due to risk of serious rash.
Timing: Prior to initiation
Routine Monitoring
Skin examination
Frequency: Regularly, especially during titration and first 8 weeks of therapy
Target: Absence of rash
Action Threshold: Any new rash, especially if accompanied by fever, lymphadenopathy, or facial swelling, requires immediate discontinuation and medical evaluation.
Seizure frequency/severity (for epilepsy)
Frequency: Ongoing, at each clinical visit
Target: Reduction in seizures
Action Threshold: Lack of efficacy may warrant dose adjustment or alternative therapy.
Mood stabilization (for bipolar disorder, if applicable)
Frequency: Ongoing, at each clinical visit
Target: Improved mood stability
Action Threshold: Lack of efficacy may warrant dose adjustment or alternative therapy.
Adverse effects monitoring
Frequency: Ongoing, at each clinical visit
Target: Tolerance
Action Threshold: Significant or intolerable side effects may require dose adjustment or discontinuation.
Symptom Monitoring
- Rash (especially widespread, blistering, or accompanied by fever, facial swelling, lymphadenopathy)
- Fever
- Sore throat
- Swollen glands
- Mouth sores
- Unusual bruising or bleeding
- Yellowing of skin or eyes (jaundice)
- Unusual tiredness or weakness
- Severe muscle pain
- Changes in vision (e.g., blurred vision, diplopia)
- Dizziness
- Ataxia
- Headache
- Nausea/vomiting
Special Patient Groups
Pregnancy
Lamotrigine crosses the placenta. While generally considered one of the safer AEDs in pregnancy, it is associated with a small increased risk of oral clefts (cleft lip/palate) when exposed during the first trimester, particularly at higher doses. However, the risk of untreated seizures or mood episodes often outweighs the potential fetal risks. Use during pregnancy should be carefully weighed against the risks of uncontrolled maternal disease. Enrollment in a pregnancy registry (e.g., North American Antiepileptic Drug Pregnancy Registry) is recommended.
Trimester-Specific Risks:
First Trimester:
Small increased risk of oral clefts (cleft lip/palate).
Second Trimester:
No specific major malformation risks identified beyond first trimester.
Third Trimester:
No specific major malformation risks identified. Maternal lamotrigine levels may decrease during pregnancy, requiring dose adjustments, and may increase postpartum.
Lactation
Lamotrigine is excreted into breast milk. While generally considered compatible with breastfeeding, infant monitoring for adverse effects (e.g., rash, drowsiness, poor feeding, apnea) is recommended, especially in neonates or infants with impaired renal/hepatic function. Therapeutic drug monitoring in the infant may be considered in some cases.
Infant Risk:
Low to moderate. Potential for drowsiness, poor feeding, rash, or apnea in the infant. Monitor infant closely.
Pediatric Use
Lamotrigine ER is approved for partial-onset seizures in patients 13 years and older. For younger pediatric patients, the immediate-release formulation is typically used, with specific dosing guidelines based on age, weight, and concomitant medications. The risk of serious rash is higher in pediatric patients (2-16 years) compared to adults.
Geriatric Use
No specific dose adjustments are generally required based solely on age, but caution is advised due to potential for age-related decreases in renal or hepatic function and increased sensitivity to adverse effects. Start with lower doses and titrate slowly, monitoring for adverse effects.
Clinical Information
Clinical Pearls
- Slow titration is paramount to minimize the risk of serious skin rash. Do not accelerate the titration schedule.
- Patients should be educated to report any rash immediately. Discontinuation is usually warranted unless the rash is clearly not drug-related.
- Lamotrigine levels are significantly affected by concomitant medications, especially valproate (increases levels) and enzyme-inducing AEDs/oral contraceptives (decrease levels). Dose adjustments are critical when adding or discontinuing these agents.
- Extended-release formulation is taken once daily and should not be crushed, chewed, or divided.
- While primarily known for epilepsy and bipolar disorder, lamotrigine is sometimes used off-label for neuropathic pain or migraine prophylaxis, though evidence varies.
Alternative Therapies
- Other antiepileptic drugs (e.g., Levetiracetam, Carbamazepine, Valproate, Oxcarbazepine, Topiramate, Gabapentin, Phenytoin)
- Other mood stabilizers (e.g., Lithium, Valproate, Carbamazepine, Atypical antipsychotics)
Cost & Coverage
Average Cost:
$50 - $200 per 30 tablets (50mg ER)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure your safety, never share your medication with others or take someone else's medication. This medication is accompanied by a Medication Guide, which provides crucial information. Please read this guide carefully and review it again whenever you receive a refill of this medication. If you have any questions or concerns about this medication, we encourage you to discuss them with your doctor, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide detailed information about the overdose, including the substance taken, the amount, and the time it occurred.