Lamictal XR 100mg 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
Not available
FDA Approved
Jul 2009
DEA Schedule
Not Controlled
Overview
What is this medicine?
Lamictal XR is an extended-release medication used to help control certain types of seizures in people 13 years and older. It works by stabilizing electrical activity in the brain. It's taken once a day.
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 closely. 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 well.
Important Administration Instructions
Swallow the medication whole; do not chew, break, or crush it.
If you have difficulty swallowing, consult your doctor for guidance.
Do not change your dose or stop taking this medication without consulting your doctor, as this may cause seizures.
If you need to stop taking this medication, your doctor will instruct you on how to gradually taper off the dose to minimize the risk of side effects.
If you stop taking this medication and need to restart it, your doctor may recommend starting at a lower dose and gradually increasing it.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light and moisture.
Keep your medication in a dry place, away from the bathroom.
Store 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 by your pharmacist.
Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in a drug take-back program in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember.
If it is close to the time for your next dose, skip the missed dose and resume your regular dosing schedule.
* Do not take two doses at the same time or take extra doses to make up for a missed dose.
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 closely. 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 well.
Important Administration Instructions
Swallow the medication whole; do not chew, break, or crush it.
If you have difficulty swallowing, consult your doctor for guidance.
Do not change your dose or stop taking this medication without consulting your doctor, as this may cause seizures.
If you need to stop taking this medication, your doctor will instruct you on how to gradually taper off the dose to minimize the risk of side effects.
If you stop taking this medication and need to restart it, your doctor may recommend starting at a lower dose and gradually increasing it.
Storing and Disposing of Your Medication
Store your medication at room temperature, protected from light and moisture.
Keep your medication in a dry place, away from the bathroom.
Store 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 by your pharmacist.
Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in a drug take-back program in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember.
If it is close to the time for your next dose, skip the missed dose and resume your regular dosing schedule.
* Do not take two doses at the same time or take extra doses to make up for a missed dose.
Lifestyle & Tips
- Take Lamictal XR exactly as prescribed, usually once daily, at the same time each day. Do not chew, crush, or divide the tablet; swallow it whole.
- Do not stop taking this medication suddenly, as it can lead to increased seizures. Any dose changes must be made slowly and under medical supervision.
- Be aware of the risk of serious skin rash. Report any new rash, fever, or flu-like symptoms to your doctor immediately.
- 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.
- Avoid alcohol, as it can worsen side effects like dizziness and drowsiness.
- If you are a woman of childbearing potential, discuss contraception options with your doctor, as oral contraceptives can affect lamotrigine levels, and lamotrigine can affect the effectiveness of some contraceptives. Also, discuss pregnancy planning due to potential risks to the fetus.
- Carry a medical alert card or wear a medical alert bracelet indicating you are taking lamotrigine.
Available Forms & Alternatives
Available Strengths:
- Lamictal 150mg Tablets
- Lamictal 200mg Tablets
- Lamictal 100mg Tablets
- Lamictal 25mg Tablets
- Lamictal 5mg Chewabl Disprsbl Tabs
- Lamictal 25mg Chewabl Disprsbl Tabs
- Lamictal Orange Strt Kit25mg/100mg
- Lamictal Blue Starter Kit 25mg
- Lamictal XR 25mg Tablets
- Lamictal XR 50mg Tablets
- Lamictal XR 100mg Tablets
- Lamictal XR 200mg Tablets
- Lamictal XR 25-50-100mg Titrtn Kit
- Lamictal XR 25-50mg Titration Kt 28
- Lamictal XR 50-100-200mg Titrtn Kit
- Lamictal ODT 25mg Tablets
- Lamictal ODT 50mg Tablets
- Lamictal ODT 100mg Tablets
- Lamictal ODT 200mg Tablets
- Lamictal ODT 25-50-100mg Tb Kt Orng
- Lamictal ODT 25-50mg Tb Kit Blue
- Lamictal ODT 50-100mg Tb Kit Green
- Lamictal Green Strt Kit 25mg/100mg
- Lamictal XR 300mg Tablets
- Lamictal XR 250mg Tablets
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Initial titration varies significantly based on concomitant medications. 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 usually 300-500 mg once daily.
Dose Range:
100 - 500 mg
Condition-Specific Dosing:
Adjunctive therapy for partial-onset seizures, primary generalized tonic-clonic seizures, or generalized seizures of Lennox-Gastaut syndrome:
Initial titration is critical and depends on concomitant medications (e.g., valproate, enzyme-inducing AEDs, non-enzyme-inducing AEDs). Maintenance dose typically 300-500 mg once daily, but can be up to 600 mg once daily in some cases.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established for Lamictal XR (approved for âĨ13 years for specific indications). For immediate-release lamotrigine, dosing is weight-based and depends on concomitant medications.
Adolescent:
For patients âĨ13 years of age, dosing is similar to adults, with a slow titration schedule based on concomitant medications. Initial dose 25 mg once daily for 2 weeks (if not on valproate or enzyme inducers).
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended.
Severe:
Use with caution. Consider a reduction in maintenance dose for patients with significant renal impairment. Specific guidelines are not well-defined, but a 25% reduction in maintenance dose may be considered.
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 recommended.
Moderate:
Consider a 25% reduction in initial, escalation, and maintenance doses.
Severe:
Consider a 50% reduction in initial, escalation, and maintenance doses.
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 modulating the release of excitatory neurotransmitters (e.g., glutamate and aspartate). It also weakly inhibits voltage-gated calcium channels.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 98% (oral)
Tmax:
Approximately 4-6 hours (for XR formulation, can be longer than IR)
FoodEffect:
Food does not significantly affect the rate or extent of absorption of Lamictal XR.
Distribution:
Vd:
Approximately 0.97-1.3 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 25-33 hours (can be significantly altered by concomitant medications: e.g., ~70 hours with valproate, ~14 hours with enzyme-inducing AEDs)
Clearance:
Approximately 0.3-0.4 mL/min/kg (highly variable based on concomitant medications)
ExcretionRoute:
Renal (approximately 94% as metabolites, 2% unchanged)
Unchanged:
Approximately 2%
Pharmacodynamics
OnsetOfAction:
Gradual, due to slow titration required to minimize rash risk. Therapeutic effects may not be seen for several weeks.
PeakEffect:
Not directly applicable due to slow titration and chronic use for seizure control.
DurationOfAction:
Once-daily dosing due to extended-release formulation and long half-life.
Safety & Warnings
BLACK BOX WARNING
Serious Skin Rashes: Life-threatening serious rashes, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), have been reported with lamotrigine. The incidence of these serious rashes is higher in pediatric patients than in adults. Factors increasing risk include concomitant use of valproate, exceeding recommended initial dose, and rapid dose escalation. Benign rashes also occur, but differentiation from serious rashes is difficult. Discontinue lamotrigine at the first sign of rash unless the rash is clearly not drug-related. Discontinuation may not prevent a rash from becoming life-threatening or permanently disabling or disfiguring.
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 or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to pass urine
+ 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
Changes in balance
Inability to control eye movements
Flu-like symptoms
Painful 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 lead to bleeding problems, 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
Changes in balance
Difficulty walking (new or worsening)
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to report any concerns to your doctor. If you experience any of the following side effects, contact your doctor or seek medical help if they bother you or persist:
Dizziness
Drowsiness
Fatigue
Weakness
Constipation
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Shakiness
Trouble sleeping
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 or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of kidney problems, including:
+ Inability to pass urine
+ 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
Changes in balance
Inability to control eye movements
Flu-like symptoms
Painful 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 lead to bleeding problems, 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
Changes in balance
Difficulty walking (new or worsening)
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to report any concerns to your doctor. If you experience any of the following side effects, contact your doctor or seek medical help if they bother you or persist:
Dizziness
Drowsiness
Fatigue
Weakness
Constipation
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Shakiness
Trouble sleeping
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 peels
- Fever, swollen glands, or flu-like symptoms
- Swelling of the face, eyes, lips, or tongue
- Sore throat or mouth sores
- Unusual bruising or bleeding
- Yellowing of the skin or eyes (jaundice)
- Dark urine or severe fatigue (signs of liver problems)
- Worsening depression, suicidal thoughts, or unusual changes in mood or behavior
- Increased seizure frequency or severity
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, 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 health problems, as these may affect the safety and efficacy of the medication
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm that it is safe to do so. This will help prevent potential interactions and ensure the medication is suitable for your specific health needs.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, 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 health problems, as these may affect the safety and efficacy of the medication
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm that it is safe to do so. This will help prevent potential interactions and ensure the medication is suitable for your specific health needs.
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, about your treatment. This will help ensure your safety and prevent potential interactions with other medications.
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 medication.
Monitoring and Lab Tests
Regular blood tests will be necessary, as directed by your doctor. Be sure to discuss any concerns or questions with your doctor. Additionally, 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 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 behavior. If you experience new or worsening symptoms such as depression, anxiety, restlessness, irritability, panic attacks, or mood changes, contact your doctor immediately. If you have suicidal thoughts or actions, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of aseptic meningitis, a severe brain problem. If you experience symptoms such as headache, fever, chills, severe nausea or vomiting, stiff neck, rash, sensitivity to light, drowsiness, or confusion, contact your doctor immediately.
Medication Verification
To avoid confusion, 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 heart rhythms, heart failure, or other heart problems, discuss the potential risks with your doctor. Abnormal heartbeats can increase the risk of sudden death in individuals with pre-existing heart conditions.
Pediatric Use
When used in children, this medication requires careful monitoring, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
If you are taking birth control pills or other hormone-based contraceptives, inform your doctor, as these medications may interact with this drug. The effectiveness of birth control pills may be reduced, and the risk of side effects may increase during the week when the pills are not active. Consider using an additional form of birth control, such as a condom, to prevent pregnancy.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the potential benefits and risks with your doctor.
Seizure Management
If your seizures change or worsen after starting this medication, consult with your doctor to adjust your treatment plan as needed.
When taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, about your treatment. This will help ensure your safety and prevent potential interactions with other medications.
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 medication.
Monitoring and Lab Tests
Regular blood tests will be necessary, as directed by your doctor. Be sure to discuss any concerns or questions with your doctor. Additionally, 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 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 behavior. If you experience new or worsening symptoms such as depression, anxiety, restlessness, irritability, panic attacks, or mood changes, contact your doctor immediately. If you have suicidal thoughts or actions, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of aseptic meningitis, a severe brain problem. If you experience symptoms such as headache, fever, chills, severe nausea or vomiting, stiff neck, rash, sensitivity to light, drowsiness, or confusion, contact your doctor immediately.
Medication Verification
To avoid confusion, 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 heart rhythms, heart failure, or other heart problems, discuss the potential risks with your doctor. Abnormal heartbeats can increase the risk of sudden death in individuals with pre-existing heart conditions.
Pediatric Use
When used in children, this medication requires careful monitoring, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
If you are taking birth control pills or other hormone-based contraceptives, inform your doctor, as these medications may interact with this drug. The effectiveness of birth control pills may be reduced, and the risk of side effects may increase during the week when the pills are not active. Consider using an additional form of birth control, such as a condom, to prevent pregnancy.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the potential benefits and risks with your doctor.
Seizure Management
If your seizures change or worsen after starting this medication, consult with your doctor to adjust your treatment plan as needed.
Overdose Information
Overdose Symptoms:
- Dizziness
- Ataxia (lack of coordination)
- Nystagmus (involuntary eye movements)
- Decreased consciousness
- Coma
- Seizures (paradoxical)
- Cardiac conduction abnormalities (e.g., QRS prolongation)
What to Do:
Seek immediate medical attention or call a poison control center (e.g., 1-800-222-1222). There is no specific antidote. Treatment is supportive, including gastric lavage, activated charcoal, and close monitoring of vital signs and cardiac function.
Drug Interactions
Major Interactions
- Valproate (increases lamotrigine levels significantly, requiring dose reduction)
- Carbamazepine (decreases lamotrigine levels, requiring dose increase)
- Phenytoin (decreases lamotrigine levels, requiring dose increase)
- Phenobarbital (decreases lamotrigine levels, requiring dose increase)
- Primidone (decreases lamotrigine levels, requiring dose increase)
- Oral contraceptives containing estrogen (decreases lamotrigine levels, requiring dose increase and potential breakthrough bleeding)
- Rifampin (decreases lamotrigine levels, requiring dose increase)
- Lopinavir/ritonavir (decreases lamotrigine levels)
- Atazanavir/ritonavir (decreases lamotrigine levels)
Moderate Interactions
- Acetaminophen (may slightly decrease lamotrigine levels with chronic high-dose use)
- Risperidone (lamotrigine may decrease risperidone levels)
- Olanzapine (lamotrigine may decrease olanzapine levels)
- Aripiprazole (lamotrigine may decrease aripiprazole levels)
- Zidovudine (lamotrigine may increase zidovudine levels)
- Dofetilide (lamotrigine may increase dofetilide 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 dysfunction (rare).
Timing: Prior to initiation
Renal Function Tests (RFTs)
Rationale: To establish baseline, especially if renal impairment is suspected.
Timing: Prior to initiation
Skin assessment
Rationale: To document baseline skin condition due to risk of serious rash.
Timing: Prior to initiation
Routine Monitoring
Clinical response (seizure frequency/severity)
Frequency: Regularly during titration and maintenance
Target: Optimal seizure control with minimal side effects
Action Threshold: Inadequate seizure control or intolerable side effects warrant dose adjustment or alternative therapy.
Adverse effects (especially rash, hypersensitivity symptoms)
Frequency: Daily during initial titration, then regularly
Target: Absence of serious rash or hypersensitivity
Action Threshold: Any new rash, fever, lymphadenopathy, facial swelling, or other signs of hypersensitivity require immediate discontinuation and medical evaluation.
Mood and behavioral changes
Frequency: Regularly
Target: Stable mood, absence of suicidal ideation
Action Threshold: Emergence or worsening of depression, suicidal thoughts, or unusual behavioral changes require immediate evaluation.
Lamotrigine plasma concentrations (Therapeutic Drug Monitoring - TDM)
Frequency: Not routinely recommended for all patients, but useful in specific situations (e.g., suspected non-adherence, drug interactions, renal/hepatic impairment, pregnancy, poor seizure control despite adequate dosing, or significant side effects).
Target: Generally 2.5-15 mcg/mL (varies by lab and clinical context)
Action Threshold: Levels outside target range, especially if correlated with clinical symptoms or lack of efficacy, may warrant dose adjustment.
Symptom Monitoring
- New or worsening skin rash (especially blistering, peeling, or widespread)
- Fever
- Swollen lymph nodes
- Swelling of face, eyes, lips, or tongue
- Sore throat
- Mouth sores
- Unusual bruising or bleeding
- Yellowing of skin or eyes (jaundice)
- Dark urine
- Severe fatigue
- New or worsening depression
- Suicidal thoughts or behavior
- Anxiety, agitation, panic attacks
- Insomnia
- Irritability
- Hostility, aggressiveness
- Impulsivity
- Restlessness
- Mania or hypomania
- Changes in seizure frequency or type
Special Patient Groups
Pregnancy
Lamotrigine is generally considered one of the safer antiepileptic drugs during pregnancy, but it is not without risk. Data from pregnancy registries suggest a low risk of major congenital malformations, but a slightly increased risk of oral clefts has been reported in some studies (though this remains controversial and not consistently found). Monotherapy is preferred over polytherapy. Dose adjustments may be needed during pregnancy due to changes in lamotrigine clearance.
Trimester-Specific Risks:
First Trimester:
Potential for increased risk of oral clefts (controversial, some studies suggest a slight increase, others do not). Risk of major congenital malformations appears low compared to other AEDs.
Second Trimester:
Clearance of lamotrigine may increase, potentially leading to decreased lamotrigine levels and increased seizure frequency. Dose adjustments may be necessary.
Third Trimester:
Clearance continues to increase. Monitor lamotrigine levels and clinical response. Levels typically return to pre-pregnancy levels postpartum, requiring dose reduction.
Lactation
Lamotrigine is excreted into breast milk. While some infants may experience adverse effects (e.g., rash, drowsiness, poor feeding), many breastfed infants show no adverse effects. Monitor the infant for rash, drowsiness, poor feeding, and poor weight gain. Weigh the benefits of breastfeeding against the potential risks.
Infant Risk:
L3 (Moderate risk) - Significant amounts excreted into milk; monitor infant for adverse effects.
Pediatric Use
Lamictal XR is approved for adjunctive therapy of partial-onset seizures, primary generalized tonic-clonic seizures, and generalized seizures of Lennox-Gastaut syndrome in patients âĨ13 years of age. The risk of serious rash is higher in pediatric patients than in adults. Careful titration is crucial. Not recommended for children under 13 years for these indications.
Geriatric Use
Use with caution. Elderly patients may be more sensitive to the adverse effects of lamotrigine, particularly dizziness and ataxia. Start with lower doses and titrate slowly. Monitor renal and hepatic function.
Clinical Information
Clinical Pearls
- The most critical aspect of lamotrigine therapy is the slow titration schedule to minimize the risk of serious skin rash. Adherence to the titration schedule is paramount.
- Dosing is highly dependent on concomitant medications, especially valproate (requires lower lamotrigine dose) and enzyme-inducing AEDs (requires higher lamotrigine dose). Always check for drug interactions before initiating or adjusting lamotrigine.
- Lamictal XR is a once-daily formulation and should be swallowed whole. Crushing or chewing will alter its extended-release properties.
- Educate patients thoroughly about the signs and symptoms of serious rash and the importance of immediate discontinuation and medical attention if a rash develops.
- Lamotrigine can cause aseptic meningitis; patients presenting with headache, fever, nausea, vomiting, and neck stiffness should be evaluated for this rare but serious adverse event.
- While TDM is not always required, it can be very useful in cases of suspected non-adherence, drug interactions, pregnancy, renal/hepatic impairment, or when optimizing therapy.
Alternative Therapies
- Other antiepileptic drugs (AEDs) for partial-onset seizures: Levetiracetam, Carbamazepine, Oxcarbazepine, Phenytoin, Topiramate, Zonisamide, Lacosamide, Perampanel, Gabapentin, Pregabalin, etc.
- Other AEDs for primary generalized tonic-clonic seizures: Valproate, Levetiracetam, Topiramate, Perampanel.
- Other AEDs for Lennox-Gastaut syndrome: Valproate, Clobazam, Rufinamide, Topiramate, Cannabidiol, Fenfluramine.
Cost & Coverage
Average Cost:
Varies widely, typically $300-$800+ per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 2 or 3 (Brand), Tier 1 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others or take someone else's medication. This medication is accompanied by a Medication Guide, which provides crucial information for patients. 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, consult 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 reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.