Lamotrigine ER 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; Mood Stabilizer
Pharmacologic Class
Phenyltriazine derivative; Voltage-gated sodium channel blocker
Pregnancy Category
Category C
FDA Approved
Jul 2006
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 prevent mood swings in people with bipolar disorder. It works by stabilizing electrical activity in the brain. Because of the risk of a serious skin rash, it's very important to start with a low dose and slowly increase it over several weeks, exactly as prescribed by your doctor.
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 feeling well.
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 instruct you on how to gradually taper off to minimize the risk of side effects.
If you stop taking this medication and need to restart, your doctor may recommend starting at a lower dose and gradually increasing it. Be sure to discuss this with your doctor.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a secure 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.
What to Do If You Miss 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 scheduled 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 the missed one.
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 feeling well.
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 instruct you on how to gradually taper off to minimize the risk of side effects.
If you stop taking this medication and need to restart, your doctor may recommend starting at a lower dose and gradually increasing it. Be sure to discuss this with your doctor.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing it in a bathroom. Keep all medications in a secure 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.
What to Do If You Miss 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 scheduled 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 the missed one.
Lifestyle & Tips
- Take exactly as prescribed; do not stop taking suddenly without consulting your doctor, as this can cause withdrawal seizures or worsening of mood.
- Do not crush, chew, or divide the extended-release tablets; swallow them whole.
- Be aware of the risk of serious skin rash; report any rash immediately to your doctor, especially if accompanied by fever, swollen glands, or facial swelling.
- Avoid activities requiring mental alertness (e.g., driving, operating machinery) until you know how the medication affects you, as it can cause dizziness or drowsiness.
- Avoid alcohol or other CNS depressants, as they can increase side effects like dizziness and drowsiness.
- If you miss a dose, take it as soon as you remember, unless it's almost time for your next dose. Do not double doses. If you miss multiple doses, contact your doctor as you may need to restart titration.
- Women of childbearing potential should discuss contraception options with their doctor, as oral contraceptives can affect lamotrigine levels.
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 is critical to minimize rash risk. For epilepsy (monotherapy, not taking enzyme-inducing AEDs or valproate): 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 varies based on indication and concomitant medications.
Dose Range:
100 - 600 mg
Condition-Specific Dosing:
epilepsy_monotherapy_no_inducers_or_valproate:
Maintenance 200-250 mg once daily.
epilepsy_adjunctive_with_enzyme_inducing_aeds:
Maintenance 300-500 mg once daily.
epilepsy_adjunctive_with_valproate:
Maintenance 100-200 mg once daily.
bipolar_disorder:
Maintenance 200 mg once daily (titration similar to epilepsy, but slower).
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Dosing for epilepsy (âĨ2 years) is weight-based and depends on concomitant medications. Titration is essential and often slower than adults. Example: 0.3 mg/kg/day for 2 weeks, then 0.6 mg/kg/day for 2 weeks, then increase by 0.6 mg/kg/day every 1-2 weeks to maintenance.
Adolescent:
Dosing for epilepsy (âĨ13 years) generally follows adult guidelines, with careful titration.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed.
Moderate:
Consider lower maintenance doses in patients with significant renal impairment.
Severe:
Consider lower maintenance doses in patients with significant renal impairment. Use with caution.
Dialysis:
Supplemental doses after dialysis are generally not required as only a small fraction is removed. Monitor clinical response.
Hepatic Impairment:
Mild:
No specific adjustment needed.
Moderate:
Reduce initial, escalation, and maintenance doses by approximately 25%.
Severe:
Reduce initial, escalation, and maintenance doses by approximately 50%. Use with caution and monitor closely.
Pharmacology
Mechanism of Action
Lamotrigine is a phenyltriazine derivative that stabilizes neuronal membranes and inhibits the release of excitatory neurotransmitters (primarily glutamate and aspartate) by blocking voltage-sensitive sodium channels. This action prevents repetitive neuronal firing and propagation of seizure activity. It may also have effects on voltage-gated calcium channels and serotonin 5-HT3 receptors.
Pharmacokinetics
Absorption:
Bioavailability:
98%
Tmax:
Approximately 4-6 hours (for immediate-release); for extended-release, Tmax is typically 6-12 hours, with a smoother plasma concentration profile.
FoodEffect:
Food does not significantly affect the rate or extent of absorption of lamotrigine ER.
Distribution:
Vd:
0.97-1.36 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 25-33 hours (monotherapy); significantly shorter (13-14 hours) with enzyme-inducing AEDs; significantly longer (59-70 hours) with valproate.
Clearance:
Approximately 30 mL/min (monotherapy); highly variable based on concomitant medications.
ExcretionRoute:
Renal (approximately 94% as metabolites, 6% unchanged)
Unchanged:
Approximately 6%
Pharmacodynamics
OnsetOfAction:
Therapeutic effects are gradual due to slow titration; seizure control or mood stabilization may take weeks to months.
PeakEffect:
Achieved after reaching stable maintenance dose, typically several weeks into therapy.
DurationOfAction:
Related to half-life; once-daily dosing for ER formulation provides 24-hour coverage.
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) and toxic epidermal necrolysis (TEN), which can be fatal. The incidence of these serious rashes is greater in pediatric patients than in adults. Other risk factors include coadministration with valproate, exceeding recommended initial doses, and exceeding recommended dose escalation.
Side Effects
Serious Side Effects: Seek Medical Help Immediately
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 medical attention right away:
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
+ Sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Immune System Problem: Hemophagocytic Lymphohistiocytosis (HLH)
This medication can cause a rare but 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
Trouble walking (new or worsening)
Other Side Effects
Most people do not experience serious side effects, but some may occur. If you notice any of the following side effects, contact your doctor or seek medical attention if they bother you or do not go away:
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 about side effects or experience any symptoms that concern you, 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 medical attention right away:
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
+ Sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Immune System Problem: Hemophagocytic Lymphohistiocytosis (HLH)
This medication can cause a rare but 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
Trouble walking (new or worsening)
Other Side Effects
Most people do not experience serious side effects, but some may occur. If you notice any of the following side effects, contact your doctor or seek medical attention if they bother you or do not go away:
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 about side effects or experience any symptoms that concern you, 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 severe, widespread, blistering, or accompanied by fever, swollen glands, or facial swelling)
- Fever, sore throat, or flu-like symptoms
- Swelling of the face, eyes, lips, or tongue
- Unusual bruising or bleeding
- Yellowing of the skin or eyes (jaundice)
- Dark urine
- Severe muscle pain or weakness
- Worsening depression, suicidal thoughts or behavior, or unusual changes in mood or behavior
- New or worsening seizures
- Severe dizziness, loss of coordination, or double vision
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 symptoms you experienced as a result of the allergy.
If you are currently taking dofetilide, as this may interact with the medication.
Additionally, to ensure safe treatment, 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 existing health problems
This information will help your doctor determine whether it is safe for you to take this medication in conjunction with your other medications and health conditions. Never start, stop, or adjust the dosage 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, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
If you are currently taking dofetilide, as this may interact with the medication.
Additionally, to ensure safe treatment, 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 existing health problems
This information will help your doctor determine whether it is safe for you to take this medication in conjunction with your other medications and health conditions. Never start, stop, or adjust the dosage 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 discuss any concerns with your doctor. Additionally, inform all your healthcare providers and lab 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 mood changes. 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-Related Warnings
If you have a history of abnormal heartbeat, heart failure, or other heart problems, discuss the risks with your doctor. Abnormal heart rhythms can occur in individuals with certain heart conditions, which may lead to sudden death.
Pediatric Use
When administering this medication to children, use caution, as the risk of certain side effects may be higher in pediatric patients.
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. 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. Use alternative forms of birth control, such as condoms, while taking this medication.
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 to adjust your treatment plan.
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 discuss any concerns with your doctor. Additionally, inform all your healthcare providers and lab 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 mood changes. 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-Related Warnings
If you have a history of abnormal heartbeat, heart failure, or other heart problems, discuss the risks with your doctor. Abnormal heart rhythms can occur in individuals with certain heart conditions, which may lead to sudden death.
Pediatric Use
When administering this medication to children, use caution, as the risk of certain side effects may be higher in pediatric patients.
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. 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. Use alternative forms of birth control, such as condoms, while taking this medication.
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 to adjust your treatment plan.
Overdose Information
Overdose Symptoms:
- Ataxia (loss of coordination)
- Nystagmus (involuntary eye movements)
- Increased seizures
- Decreased consciousness
- Coma
- Dizziness
- Headache
- Tachycardia
What to Do:
Seek immediate medical attention or call 911. Contact a poison control center (1-800-222-1222). Management is supportive; there is no specific antidote. Hemodialysis is not effective in removing lamotrigine.
Drug Interactions
Major Interactions
- Valproate (increases lamotrigine levels, significantly increases risk of serious rash)
- Carbamazepine (decreases lamotrigine levels)
- Phenytoin (decreases lamotrigine levels)
- Phenobarbital (decreases lamotrigine levels)
- Primidone (decreases lamotrigine levels)
- Rifampin (decreases lamotrigine levels)
- Estrogen-containing oral contraceptives (decrease lamotrigine levels)
Moderate Interactions
- Lopinavir/ritonavir (decreases lamotrigine levels)
- Atazanavir/ritonavir (decreases lamotrigine levels)
- Dofetilide (potential for increased dofetilide levels, though clinical significance unclear)
- Paroxetine (may increase lamotrigine levels, though clinical significance often minor)
Minor Interactions
- Risperidone (lamotrigine may decrease risperidone levels, minor clinical significance)
- Olanzapine (lamotrigine may decrease olanzapine levels, minor clinical significance)
Monitoring
Baseline Monitoring
Complete Blood Count (CBC)
Rationale: To establish baseline and monitor for potential hematologic abnormalities (e.g., blood dyscrasias) which are rare but serious.
Timing: Prior to initiation
Liver Function Tests (LFTs)
Rationale: To establish baseline and monitor for potential hepatic dysfunction.
Timing: Prior to initiation
Renal Function Tests (Creatinine, BUN)
Rationale: To establish baseline, especially if renal impairment is suspected or present.
Timing: Prior to initiation
Skin Examination
Rationale: To establish baseline skin condition and educate patient on rash monitoring.
Timing: Prior to initiation
Routine Monitoring
Skin Examination/Patient Education on Rash
Frequency: Daily during titration, then routinely with patient visits
Target: Absence of new or worsening rash
Action Threshold: Any new rash, especially if accompanied by fever, lymphadenopathy, or facial swelling, requires immediate medical evaluation and potential discontinuation.
Seizure Frequency/Severity (for epilepsy)
Frequency: At each clinical visit
Target: Reduction in seizure frequency/severity
Action Threshold: Worsening seizures or inadequate control may require dose adjustment or alternative therapy.
Mood Stability/Symptoms (for bipolar disorder)
Frequency: At each clinical visit
Target: Stabilization of mood, reduction in depressive/manic symptoms
Action Threshold: Worsening mood symptoms, emergence of suicidal ideation, or inadequate control may require dose adjustment or alternative therapy.
Adverse Effects (e.g., dizziness, ataxia, blurred vision, headache, nausea)
Frequency: At each clinical visit
Target: Tolerable side effect profile
Action Threshold: Intolerable side effects may require dose reduction or discontinuation.
Therapeutic Drug Monitoring (TDM)
Frequency: Not routinely recommended, but may be useful in specific situations (e.g., suspected non-adherence, drug interactions, pregnancy, renal/hepatic impairment, treatment failure, or toxicity).
Target: Typically 2.5-15 mcg/mL (variable, clinical correlation is key)
Action Threshold: Levels outside expected range, especially if correlated with clinical symptoms or lack of efficacy, may warrant dose adjustment.
Symptom Monitoring
- Skin rash (especially if severe, widespread, blistering, or accompanied by fever, swollen glands, facial swelling, or mouth sores)
- Fever
- Sore throat
- Swollen lymph nodes
- Facial swelling
- Unusual bruising or bleeding
- Yellowing of skin or eyes (jaundice)
- Dark urine
- Severe muscle pain
- Worsening depression or suicidal thoughts/behavior
- New or worsening anxiety, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, akathisia, hypomania, or mania
- Changes in seizure pattern
- Dizziness, ataxia, blurred vision, double vision
Special Patient Groups
Pregnancy
Lamotrigine is generally considered one of the safer antiepileptic drugs during pregnancy, particularly for monotherapy, but it is still a Category C drug. Use during pregnancy should only occur if the potential benefit justifies the potential risk to the fetus. Patients should be enrolled in pregnancy registries.
Trimester-Specific Risks:
First Trimester:
Increased risk of oral clefts (cleft lip/palate) has been reported in some studies, particularly with higher doses or polytherapy, though more recent data suggest the risk is lower than initially thought and may not be significantly different from the general population. Neural tube defects are not significantly increased.
Second Trimester:
Generally considered safer than the first trimester for organogenesis, but continued monitoring of maternal lamotrigine levels may be necessary as levels can decrease during pregnancy, potentially leading to loss of seizure control.
Third Trimester:
Maternal lamotrigine levels may continue to decrease. Monitor for potential withdrawal symptoms in the neonate if maternal levels are high at delivery, though this is rare. Consider vitamin K supplementation for the mother in the last month of pregnancy to prevent neonatal coagulopathy, as with other AEDs.
Lactation
Lamotrigine is excreted into breast milk. The amount varies, but infant serum concentrations can be significant. Weigh the benefits of breastfeeding against the potential risks to the infant. Monitor the infant for adverse effects.
Infant Risk:
L3 (Moderate risk). Potential for adverse effects in the infant, including rash, drowsiness, poor feeding, and apnea. Monitor the infant for these symptoms. Therapeutic drug monitoring of infant serum levels may be considered if concerns arise.
Pediatric Use
Higher incidence of serious rash (SJS/TEN) compared to adults, especially in children under 16 years. Strict adherence to slow titration schedules is crucial. Dosing is weight-based and complex, requiring careful calculation and monitoring. Not approved for bipolar disorder in pediatric patients.
Geriatric Use
Use with caution. Start with lower doses and titrate slowly, as elderly patients may have reduced renal or hepatic function, which can affect lamotrigine clearance. Monitor for increased susceptibility to adverse effects like dizziness and ataxia.
Clinical Information
Clinical Pearls
- The most critical aspect of lamotrigine therapy is the slow, gradual titration to minimize the risk of serious, life-threatening skin rashes (SJS/TEN). Any deviation from the recommended titration schedule, especially rapid dose escalation or restarting at a high dose after a missed period, significantly increases this risk.
- Concomitant medications, particularly valproate (which increases lamotrigine levels) and enzyme-inducing AEDs or oral contraceptives (which decrease lamotrigine levels), necessitate significant adjustments to the lamotrigine dosing schedule.
- Patients must be thoroughly educated on the signs and symptoms of serious rash and instructed to seek immediate medical attention if any rash develops, especially if accompanied by fever, facial swelling, or lymphadenopathy.
- Lamotrigine ER offers once-daily dosing and a smoother pharmacokinetic profile compared to immediate-release, which may improve adherence and reduce peak-related side effects.
Alternative Therapies
- For Epilepsy: Levetiracetam, Carbamazepine, Oxcarbazepine, Valproate, Topiramate, Zonisamide, Gabapentin, Pregabalin, Phenytoin, Phenobarbital.
- For Bipolar Disorder (Mood Stabilizers): Lithium, Valproate, Carbamazepine, Quetiapine, Olanzapine, Lurasidone, Cariprazine.
Cost & Coverage
Average Cost:
Check current per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. 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 about its use. Please read this guide carefully and review it again whenever you receive a refill. If you have any questions or concerns about this medication, don't hesitate 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. Be prepared to provide detailed information about the overdose, including the medication taken, the amount, and the time it occurred.
This medication is accompanied by a Medication Guide, which provides crucial information about its use. Please read this guide carefully and review it again whenever you receive a refill. If you have any questions or concerns about this medication, don't hesitate 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. Be prepared to provide detailed information about the overdose, including the medication taken, the amount, and the time it occurred.