Lamotrigine 300mg ER 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
C
FDA Approved
Jun 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 prevent mood swings in adults with bipolar I 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 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 alter your 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 the dose 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.
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 local drug take-back program.
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 alter your 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 the dose 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.
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 local drug take-back program.
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 exactly as prescribed; do not stop suddenly without consulting your doctor, as this can worsen seizures or mood symptoms.
- Do not crush, chew, or divide extended-release tablets; swallow them whole.
- Report any new skin rash immediately to your doctor, as it could be serious.
- Avoid activities requiring mental alertness (e.g., driving, operating machinery) until you know how this medication affects you, as it can cause dizziness or drowsiness.
- Limit or avoid alcohol consumption, as it can increase side effects.
- If you are a woman of childbearing potential, discuss contraception with your doctor, as lamotrigine levels can be affected by hormonal contraceptives, and pregnancy planning is important.
- 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:
Maintenance dose for epilepsy (adjunctive or monotherapy) or bipolar I disorder. Dosing must be titrated slowly over several weeks to minimize risk of serious rash. The 300mg ER tablet is typically a maintenance dose reached after titration.
Dose Range:
100 - 600 mg
Condition-Specific Dosing:
epilepsy_adjunctive_therapy_without_valproate_or_enzyme_inducers:
Initial: 25 mg ER daily for 2 weeks, then 50 mg ER daily for 2 weeks, then 100 mg ER daily for 1 week, then 150 mg ER daily for 1 week, then 200 mg ER daily. Maintenance: 200-600 mg ER daily (divided into 1-2 doses).
epilepsy_adjunctive_therapy_with_valproate:
Initial: 25 mg ER every other day for 2 weeks, then 25 mg ER daily for 2 weeks, then 50 mg ER daily for 1 week, then 75 mg ER daily for 1 week, then 100 mg ER daily. Maintenance: 100-250 mg ER daily (divided into 1-2 doses).
epilepsy_adjunctive_therapy_with_enzyme_inducers_without_valproate:
Initial: 50 mg ER daily for 2 weeks, then 100 mg ER daily for 2 weeks, then 200 mg ER daily for 1 week, then 300 mg ER daily for 1 week, then 400 mg ER daily. Maintenance: 400-600 mg ER daily (divided into 1-2 doses).
bipolar_i_disorder_without_valproate_or_enzyme_inducers:
Initial: 25 mg ER daily for 2 weeks, then 50 mg ER daily for 2 weeks, then 100 mg ER daily for 1 week, then 150 mg ER daily for 1 week, then 200 mg ER daily. Maintenance: 200-400 mg ER daily (divided into 1-2 doses).
bipolar_i_disorder_with_valproate:
Initial: 25 mg ER every other day for 2 weeks, then 25 mg ER daily for 2 weeks, then 50 mg ER daily for 1 week, then 75 mg ER daily for 1 week, then 100 mg ER daily. Maintenance: 100-200 mg ER daily (divided into 1-2 doses).
bipolar_i_disorder_with_enzyme_inducers_without_valproate:
Initial: 50 mg ER daily for 2 weeks, then 100 mg ER daily for 2 weeks, then 200 mg ER daily for 1 week, then 300 mg ER daily for 1 week, then 400 mg ER daily. Maintenance: 400 mg ER daily (divided into 1-2 doses).
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established for ER formulation. IR formulation is used for children âĨ2 years for epilepsy, with weight-based and concomitant medication-dependent dosing.
Adolescent:
For adolescents (âĨ13 years) with epilepsy or bipolar I disorder, follow adult dosing guidelines based on concomitant medications.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended, but caution advised.
Severe:
Consider a reduction in maintenance dose (e.g., 25% reduction). Monitor clinical response and adverse effects.
Dialysis:
Supplemental doses after dialysis are not required. Monitor clinical response and adverse effects.
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. Monitor clinical response and adverse effects.
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 reduces the propagation of seizure activity. It may also weakly inhibit voltage-gated calcium channels and modulate serotonin 5-HT3 receptors.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 98% (oral)
Tmax:
6-12 hours (Extended-Release formulation)
FoodEffect:
Food does not significantly affect the rate or extent of absorption of Lamotrigine ER.
Distribution:
Vd:
0.97-1.3 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 25-33 hours (monotherapy); ~15 hours (with enzyme inducers); ~59 hours (with valproate)
Clearance:
Approximately 0.3-0.4 mL/min/kg (monotherapy)
ExcretionRoute:
Renal (urine)
Unchanged:
Approximately 10% (unchanged drug in urine)
Pharmacodynamics
OnsetOfAction:
Weeks (due to slow titration)
PeakEffect:
Weeks to months (after reaching stable maintenance dose)
DurationOfAction:
24 hours (due to ER formulation and half-life)
Safety & Warnings
BLACK BOX WARNING
Serious Skin Rashes: Lamotrigine can cause serious skin 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 rashes is higher in pediatric patients than in adults. Other risk factors include co-administration with 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. Therefore, lamotrigine should ordinarily be discontinued at the first sign of rash, unless the rash is clearly not drug-related.
Side Effects
Serious 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 medical attention immediately:
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
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)
In rare cases, this medication can cause a life-threatening immune system problem called hemophagocytic lymphohistiocytosis (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
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 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 side effects not listed here, 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 immediately:
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
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)
In rare cases, this medication can cause a life-threatening immune system problem called hemophagocytic lymphohistiocytosis (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
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 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 side effects not listed here, 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 (even mild)
- Fever, swollen glands, or flu-like symptoms
- Sore throat or mouth sores
- Swelling of the face, eyes, lips, or tongue
- Unusual bruising or bleeding
- Yellowing of the skin or eyes (jaundice)
- Severe muscle pain or weakness
- New or worsening depression, anxiety, or agitation
- Thoughts of self-harm or suicide
- Unusual changes in behavior or mood
- Signs of liver problems (e.g., nausea, vomiting, dark urine, stomach pain)
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.
To ensure safe treatment, 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 existing health problems
This information will help your doctor determine whether it is safe 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 that 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.
To ensure safe treatment, 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 existing health problems
This information will help your doctor determine whether it is safe 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 that it is safe to do so.
Precautions & Cautions
Important Warnings and Cautions
General Precautions
Inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Avoid driving and other activities that require alertness until you understand how this medication affects you.
It may take several weeks to experience the full effects of this medication.
Regular blood tests are necessary to monitor your condition. Follow your doctor's instructions for scheduling these tests.
This medication may interfere with certain laboratory tests. Inform all your healthcare providers and lab personnel that you are taking this medication.
Before consuming alcohol, marijuana, or other forms of cannabis, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor.
Mental Health and Suicidal Thoughts
Like other medications used to treat seizures, this medication may rarely increase the risk of suicidal thoughts or behaviors. This risk may be higher in individuals with a history of suicidal thoughts or behaviors.
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 behaviors, contact your doctor right away.
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 Safety
Verify that you have the correct medication by checking the shape, color, size, and labeling. If you notice any changes, consult your pharmacist.
Be aware that some medications may have similar names or appearances. Always ensure you have the correct medication.
Heart Conditions
If you have an abnormal heartbeat, heart failure, or other heart problems, discuss your condition with your doctor.
Abnormal heart rhythms can occur in individuals with certain heart conditions, which may lead to sudden death.
Pediatric Use
If the patient is a child, use this medication with caution. Children may be at a higher risk for certain side effects.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult your doctor before starting or stopping any hormone-based birth control.
The risk of side effects may be increased when taking birth control pills during the week when the pills are inactive. Discuss this with your doctor.
Birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an additional 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 your doctor.
General Precautions
Inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Avoid driving and other activities that require alertness until you understand how this medication affects you.
It may take several weeks to experience the full effects of this medication.
Regular blood tests are necessary to monitor your condition. Follow your doctor's instructions for scheduling these tests.
This medication may interfere with certain laboratory tests. Inform all your healthcare providers and lab personnel that you are taking this medication.
Before consuming alcohol, marijuana, or other forms of cannabis, or taking prescription or over-the-counter medications that may cause drowsiness, consult your doctor.
Mental Health and Suicidal Thoughts
Like other medications used to treat seizures, this medication may rarely increase the risk of suicidal thoughts or behaviors. This risk may be higher in individuals with a history of suicidal thoughts or behaviors.
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 behaviors, contact your doctor right away.
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 Safety
Verify that you have the correct medication by checking the shape, color, size, and labeling. If you notice any changes, consult your pharmacist.
Be aware that some medications may have similar names or appearances. Always ensure you have the correct medication.
Heart Conditions
If you have an abnormal heartbeat, heart failure, or other heart problems, discuss your condition with your doctor.
Abnormal heart rhythms can occur in individuals with certain heart conditions, which may lead to sudden death.
Pediatric Use
If the patient is a child, use this medication with caution. Children may be at a higher risk for certain side effects.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult your doctor before starting or stopping any hormone-based birth control.
The risk of side effects may be increased when taking birth control pills during the week when the pills are inactive. Discuss this with your doctor.
Birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an additional 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 your doctor.
Overdose Information
Overdose Symptoms:
- Dizziness
- Ataxia (loss 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. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment is supportive and may include 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, Phenytoin, Phenobarbital, Primidone (enzyme inducers, decrease lamotrigine levels, requiring dose increase)
- Oral Contraceptives (estrogen-containing, decrease lamotrigine levels, requiring dose increase)
Moderate Interactions
- Rifampin (decreases lamotrigine levels)
- Lopinavir/Ritonavir (decreases lamotrigine levels)
- Atazanavir/Ritonavir (decreases lamotrigine levels)
- Risperidone (lamotrigine may decrease risperidone levels)
- Olanzapine (lamotrigine may decrease olanzapine levels)
- Lithium (potential for additive CNS effects, monitor for toxicity)
- Paroxetine (may decrease lamotrigine clearance)
Minor Interactions
- Acetaminophen (may slightly decrease lamotrigine levels with chronic high-dose use)
- Folic acid antagonists (e.g., trimethoprim, methotrexate) - theoretical interaction due to lamotrigine's weak dihydrofolate reductase inhibition, but not clinically significant at therapeutic doses.
Monitoring
Baseline Monitoring
Baseline renal and hepatic function tests
Rationale: To establish baseline for patients with pre-existing impairment and guide potential dose adjustments.
Timing: Prior to initiation of therapy
Complete Blood Count (CBC) with differential
Rationale: Although rare, lamotrigine can cause blood dyscrasias (e.g., neutropenia, aplastic anemia).
Timing: Prior to initiation of therapy
Routine Monitoring
Clinical response (seizure frequency/severity, mood stability)
Frequency: Regularly during titration and maintenance
Target: Individualized, aiming for optimal control with minimal side effects
Action Threshold: Lack of efficacy or intolerable side effects warrant dose adjustment or re-evaluation.
Adverse effects monitoring (especially skin rash)
Frequency: Daily during titration, then regularly
Target: Absence of rash or other hypersensitivity symptoms
Action Threshold: Any new rash should prompt immediate discontinuation and medical evaluation due to risk of SJS/TEN.
Plasma lamotrigine levels (Therapeutic Drug Monitoring - TDM)
Frequency: As needed (e.g., in cases of suspected toxicity, lack of efficacy, significant drug interactions, or renal/hepatic impairment)
Target: Not routinely recommended, but typically 2-20 mcg/mL for epilepsy. Correlation between levels and efficacy/toxicity is variable.
Action Threshold: Levels outside typical range, or clinical signs/symptoms not correlating with expected response.
Mood and behavioral changes (including suicidal ideation)
Frequency: Regularly, especially during initial therapy and dose changes
Target: Stable mood, absence of suicidal thoughts or unusual behavior changes
Action Threshold: Emergence or worsening of depression, suicidal thoughts, or unusual behavior requires immediate evaluation.
Symptom Monitoring
- Skin rash (any type, especially blistering or widespread)
- Fever
- Swollen lymph nodes (lymphadenopathy)
- Facial swelling
- Sore throat
- Mouth sores
- Unusual bruising or bleeding
- Yellowing of skin or eyes (jaundice)
- Dark urine
- Severe muscle pain
- New or worsening depression
- Suicidal thoughts or behavior
- Unusual changes in mood or behavior
- Signs of hypersensitivity reaction (e.g., multi-organ failure, DRESS syndrome)
Special Patient Groups
Pregnancy
Lamotrigine is classified as Pregnancy Category C. Data from pregnancy registries suggest that the overall risk of major congenital malformations is not significantly increased compared to the general population, but there may be a slightly increased risk of oral clefts (e.g., cleft lip/palate), particularly with higher doses or polytherapy. However, the benefits of seizure control often outweigh the potential risks. Discontinuation of antiepileptic drugs during pregnancy should be avoided unless the benefits outweigh the risks.
Trimester-Specific Risks:
First Trimester:
Potential for slightly increased risk of oral clefts. Folic acid supplementation is generally recommended for all women of childbearing potential taking antiepileptic drugs.
Second Trimester:
Not available
Third Trimester:
Not available
Lactation
Lamotrigine is excreted into breast milk. The concentration in breast milk can be significant, and infant serum levels can reach therapeutic or subtherapeutic ranges. Monitor breastfed infants for adverse effects such as rash, apnea, drowsiness, poor feeding, and poor weight gain. Weigh the benefits of breastfeeding against the potential risks to the infant.
Infant Risk:
L3 (Moderately Safe) - Monitor infant for adverse effects. Consider therapeutic drug monitoring in the infant if concerns arise.
Pediatric Use
Lamotrigine ER is approved for adjunctive treatment of partial seizures in patients 13 years and older, and for generalized tonic-clonic seizures and Lennox-Gastaut syndrome in patients 13 years and older. The IR formulation is approved for children âĨ2 years for certain seizure types. Pediatric patients, especially those under 16, have a higher risk of serious rash. Dosing is weight-based and depends on concomitant medications.
Geriatric Use
No specific dose adjustment is generally required based on age alone, but elderly patients may have reduced renal or hepatic function, which could necessitate dose adjustments. Start with lower doses and titrate slowly. Monitor for increased sensitivity to adverse effects, particularly dizziness and ataxia, and potential drug interactions due to polypharmacy.
Clinical Information
Clinical Pearls
- The slow titration schedule is critical to minimize the risk of serious, life-threatening skin rashes (SJS/TEN). Emphasize patient adherence to the titration schedule.
- Concomitant medications, especially valproate (increases lamotrigine levels) and enzyme-inducing AEDs/oral contraceptives (decrease lamotrigine levels), significantly impact lamotrigine dosing and require careful adjustment.
- Lamotrigine ER is designed for once-daily dosing and should be swallowed whole; crushing or chewing can lead to rapid release and potential toxicity.
- Any new rash, regardless of appearance, should prompt immediate discontinuation of lamotrigine and medical evaluation.
- Lamotrigine is effective for both seizure control and mood stabilization in bipolar disorder, making it a versatile option for patients with comorbid conditions.
- Patients should be educated about the signs and symptoms of hypersensitivity reactions, including DRESS syndrome, which can involve multiple organ systems.
Alternative Therapies
- For Epilepsy: Levetiracetam, Carbamazepine, Oxcarbazepine, Valproate, Topiramate, Phenytoin, Gabapentin, Pregabalin, Zonisamide, Lacosamide.
- For Bipolar Disorder (Mood Stabilizers): Lithium, Valproate, Carbamazepine, Atypical Antipsychotics (e.g., Olanzapine, Quetiapine, Aripiprazole, Lurasidone).
Cost & Coverage
Average Cost:
Not available (highly variable, check current pharmacy pricing) per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Generic formulations are typically covered as Tier 1 or Tier 2 by most insurance plans. Brand-name Lamictal XR may be Tier 3 or higher.
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 is a valuable resource that provides important information about your treatment. Please read this guide carefully and review it again whenever you receive a refill of your medication. If you have any questions or concerns about your medication, don't hesitate to discuss them with your doctor, pharmacist, or other healthcare provider.
In the event of a suspected overdose, it's crucial to seek immediate medical attention. Call your local poison control center or visit the emergency room right away. When seeking help, be prepared to provide detailed information about the overdose, including the name of the medication taken, the amount consumed, and the time it occurred.
This medication is accompanied by a Medication Guide, which is a valuable resource that provides important information about your treatment. Please read this guide carefully and review it again whenever you receive a refill of your medication. If you have any questions or concerns about your medication, don't hesitate to discuss them with your doctor, pharmacist, or other healthcare provider.
In the event of a suspected overdose, it's crucial to seek immediate medical attention. Call your local poison control center or visit the emergency room right away. When seeking help, be prepared to provide detailed information about the overdose, including the name of the medication taken, the amount consumed, and the time it occurred.