Lamictal 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. @ COMMON USES: It is used to help control certain kinds of seizures.It is used to treat bipolar disorder.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
Dec 1994
DEA Schedule
Not Controlled
Overview
What is this medicine?
Lamotrigine is a medication used to treat certain types of seizures (epilepsy) and to help prevent extreme mood swings in people with bipolar disorder. It works by stabilizing electrical activity in the brain.
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 with your prescription and follow the instructions exactly. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
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 with a lower dose and gradually increasing it.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and moisture.
Keep your medication in a dry place, such as a closet or drawer, and avoid storing it in the bathroom.
Keep all medications out of the reach of children and pets.
Dispose of unused or expired medication by throwing it away in a secure location.
Do not flush medication down the toilet or pour it down the drain unless instructed to do so by your pharmacist or healthcare provider.
Check with your pharmacist to see if there are any medication 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.
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 with your prescription and follow the instructions exactly. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
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 with a lower dose and gradually increasing it.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and moisture.
Keep your medication in a dry place, such as a closet or drawer, and avoid storing it in the bathroom.
Keep all medications out of the reach of children and pets.
Dispose of unused or expired medication by throwing it away in a secure location.
Do not flush medication down the toilet or pour it down the drain unless instructed to do so by your pharmacist or healthcare provider.
Check with your pharmacist to see if there are any medication 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.
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 cause seizures or worsening mood.
- Report any new skin rash immediately to your doctor, as it could be serious.
- Avoid driving or operating machinery until you know how this medication affects you, as it can cause dizziness or blurred vision.
- Inform your doctor about all other medications you are taking, especially birth control pills or other seizure medications, as they can affect lamotrigine levels.
- If you miss a dose, take it as soon as you remember, unless it's almost time for your next dose. Do not double dose.
- Carry a medical alert card or wear a bracelet indicating you take lamotrigine, especially if you have epilepsy.
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:
Titration required. For epilepsy (monotherapy): Initial 25 mg once daily for 2 weeks, then 50 mg once daily for 2 weeks, then 100 mg once daily for 1 week, then 200 mg once daily. Maintenance: 200-400 mg/day in 1-2 divided doses. For bipolar disorder: Initial 25 mg once daily for 2 weeks, then 50 mg once daily for 2 weeks, then 100 mg once daily for 1 week, then 200 mg once daily. Maintenance: 100-400 mg/day in 1-2 divided doses.
Dose Range:
25 - 400 mg
Condition-Specific Dosing:
concomitant_valproate:
Reduce initial dose and titration rate (e.g., 12.5 mg every other day initially).
concomitant_enzyme_inducers:
Increase initial dose and titration rate (e.g., 50 mg once daily initially).
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established for <2 years old. For 2-12 years, dosing is weight-based and depends on concomitant medications.
Child:
For epilepsy (2-12 years, with enzyme-inducing AEDs without valproate): Initial 2 mg/kg/day in 2 divided doses for 2 weeks, then 5 mg/kg/day for 2 weeks, then target 5-15 mg/kg/day. Max 400 mg/day. With valproate: Initial 0.15 mg/kg/day in 1-2 divided doses for 2 weeks, then 0.3 mg/kg/day for 2 weeks, then target 1-5 mg/kg/day. Max 200 mg/day.
Adolescent:
Dosing similar to adults, but titration may be slower for younger adolescents.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed.
Moderate:
Consider reduced maintenance doses in patients with significant renal impairment.
Severe:
Consider reduced maintenance doses (e.g., 25% to 50% reduction) in patients with significant renal impairment. Monitor clinical response.
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%. Monitor clinical response and plasma levels if available.
Pharmacology
Mechanism of Action
Lamotrigine is a phenyltriazine derivative that inhibits voltage-sensitive sodium channels, thereby stabilizing neuronal membranes and inhibiting the release of excitatory neurotransmitters (e.g., glutamate and aspartate). It also weakly inhibits voltage-gated calcium channels.
Pharmacokinetics
Absorption:
Bioavailability:
98%
Tmax:
1.4 to 4.8 hours (oral)
FoodEffect:
Food does not significantly affect the rate or extent of absorption.
Distribution:
Vd:
0.97 to 1.36 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 25-33 hours (monotherapy); significantly affected by concomitant medications (e.g., ~15 hours with enzyme inducers, ~59 hours with valproate).
Clearance:
Approximately 0.3 mL/min/kg (monotherapy)
ExcretionRoute:
Renal (approximately 94% as metabolites, 2% unchanged)
Unchanged:
Approximately 2%
Pharmacodynamics
OnsetOfAction:
Gradual, due to required titration (weeks to months for full therapeutic effect).
PeakEffect:
Achieved at steady-state concentrations, typically after several weeks of titration.
DurationOfAction:
Related to half-life; effects persist as long as therapeutic concentrations are maintained.
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 result in death. The incidence of these rashes is higher in pediatric patients than in adults. Other serious rashes, including Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome, have also been reported. The risk of serious rash is increased by: (1) coadministration with valproate, (2) exceeding recommended initial doses or dose escalation, and (3) a history of allergy or rash to other antiepileptic drugs. 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. Discontinuation of treatment 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 immediately or seek medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or 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, or swelling in the arms or legs
Severe muscle pain or weakness
Severe joint pain or swelling
Changes in vision
Chest pain or pressure
Abnormal heartbeat (fast, slow, or irregular)
Severe dizziness or fainting
Balance problems
Uncontrolled eye movements
Flu-like symptoms
Painful periods or 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
Balance problems
Difficulty walking (new or worsening)
Other Side Effects
Most people taking this medication do not experience severe side effects. However, 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, or weakness
Constipation, diarrhea, stomach pain, upset stomach, vomiting, or decreased appetite
Shakiness
Sleep disturbances
Nose or throat irritation
Weight loss
Dry mouth
Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek medical attention:
Signs of an allergic reaction, such as:
+ Rash or hives
+ Itching or red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing or tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness or 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, or swelling in the arms or legs
Severe muscle pain or weakness
Severe joint pain or swelling
Changes in vision
Chest pain or pressure
Abnormal heartbeat (fast, slow, or irregular)
Severe dizziness or fainting
Balance problems
Uncontrolled eye movements
Flu-like symptoms
Painful periods or 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
Balance problems
Difficulty walking (new or worsening)
Other Side Effects
Most people taking this medication do not experience severe side effects. However, 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, or weakness
Constipation, diarrhea, stomach pain, upset stomach, vomiting, or decreased appetite
Shakiness
Sleep disturbances
Nose or throat irritation
Weight loss
Dry mouth
Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Any new skin rash (red spots, blisters, peeling skin)
- 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)
- Severe muscle pain or weakness
- Worsening depression, anxiety, or thoughts of self-harm
- New or worsening seizures
- Severe dizziness or loss of coordination
- Blurred 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.
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 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 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 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 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 that 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 using 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 thoughts or behaviors. 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 a severe brain condition called aseptic meningitis. 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 ensure you have the correct medication, always verify the product's appearance, shape, color, size, and labeling. If you notice any changes, consult with your pharmacist.
Heart-Related Warnings
If you have an abnormal heartbeat, heart failure, or other heart problems, discuss the risks with your doctor. Abnormal heartbeats can increase the risk of sudden death in individuals with pre-existing heart conditions.
Pediatric Use
When using this medication in children, exercise caution, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult with your doctor before starting or stopping any hormone-based birth control. The risk of side effects may increase during the week when birth control pills are not active. Additionally, birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an alternative form of birth control, such as a condom, to minimize the risk of pregnancy.
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 as needed.
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 using 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 thoughts or behaviors. 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 a severe brain condition called aseptic meningitis. 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 ensure you have the correct medication, always verify the product's appearance, shape, color, size, and labeling. If you notice any changes, consult with your pharmacist.
Heart-Related Warnings
If you have an abnormal heartbeat, heart failure, or other heart problems, discuss the risks with your doctor. Abnormal heartbeats can increase the risk of sudden death in individuals with pre-existing heart conditions.
Pediatric Use
When using this medication in children, exercise caution, as the risk of certain side effects may be higher in this population.
Birth Control and Hormone Interactions
Birth control pills and other hormone-based contraceptives may affect the levels of this medication in your body. Consult with your doctor before starting or stopping any hormone-based birth control. The risk of side effects may increase during the week when birth control pills are not active. Additionally, birth control pills and other hormone-based contraceptives may be less effective in preventing pregnancy when taking this medication. Use an alternative form of birth control, such as a condom, to minimize the risk of pregnancy.
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 as needed.
Overdose Information
Overdose Symptoms:
- Dizziness
- Ataxia (loss of coordination)
- Nystagmus (involuntary eye movements)
- Decreased consciousness
- Coma
- Seizures
- Cardiac conduction abnormalities (e.g., QRS prolongation)
What to Do:
Seek immediate medical attention or call Poison Control (1-800-222-1222). Management is supportive, including gastric lavage, activated charcoal, and close monitoring of vital signs and cardiac function. There is no specific antidote.
Drug Interactions
Major Interactions
- Valproate (valproic acid, divalproex sodium): Significantly increases lamotrigine half-life and plasma levels, requiring substantial lamotrigine dose reduction to avoid toxicity (e.g., rash).
- Oral contraceptives (estrogen-containing): May decrease lamotrigine plasma levels by up to 50%, potentially leading to loss of seizure control or mood stabilization. Requires lamotrigine dose increase.
- Rifampin: Significantly decreases lamotrigine plasma levels, requiring lamotrigine dose increase.
- Carbamazepine, Phenytoin, Phenobarbital, Primidone: Enzyme inducers that decrease lamotrigine plasma levels, requiring lamotrigine dose increase.
Moderate Interactions
- Lopinavir/ritonavir: May decrease lamotrigine plasma levels.
- Atazanavir/ritonavir: May decrease lamotrigine plasma levels.
- Risperidone: Co-administration may increase risperidone levels and decrease lamotrigine levels, though clinical significance varies.
- Paracetamol (acetaminophen): High doses may slightly decrease lamotrigine levels.
Monitoring
Baseline Monitoring
Renal and Hepatic Function Tests (BUN, Creatinine, ALT, AST, Bilirubin)
Rationale: To establish baseline organ function and guide initial dosing, especially in patients with pre-existing impairment.
Timing: Prior to initiation of therapy.
Complete Blood Count (CBC) with differential
Rationale: Although rare, lamotrigine can cause hematologic abnormalities (e.g., neutropenia, aplastic anemia).
Timing: Prior to initiation of therapy.
Skin assessment
Rationale: To document baseline skin condition, given the risk of serious rash.
Timing: Prior to initiation of therapy.
Routine Monitoring
Clinical response (seizure frequency/severity, mood stability)
Frequency: Regularly during titration and maintenance, at each follow-up visit.
Target: Optimal seizure control with minimal side effects; stable mood.
Action Threshold: Worsening symptoms, lack of efficacy, or intolerable side effects warrant dose adjustment or re-evaluation.
Adverse effects monitoring (especially rash, fever, lymphadenopathy, signs of DRESS syndrome)
Frequency: Daily during initial titration, then regularly at follow-up visits.
Target: Absence of serious skin reactions or systemic hypersensitivity.
Action Threshold: Any new rash, fever, facial swelling, or lymphadenopathy requires immediate discontinuation and medical evaluation.
Suicidal ideation/behavior
Frequency: Regularly, especially during initial therapy and dose changes.
Target: Absence of suicidal thoughts or behaviors.
Action Threshold: Any report of suicidal ideation or behavior requires immediate clinical assessment and intervention.
Lamotrigine plasma levels (Therapeutic Drug Monitoring - TDM)
Frequency: Not routinely recommended for all patients, but useful in specific situations (e.g., suspected toxicity, lack of efficacy, significant drug interactions, renal/hepatic impairment, pregnancy).
Target: Typically 3-14 mcg/mL for epilepsy, but varies by indication and individual response.
Action Threshold: Levels outside the therapeutic range or inconsistent with clinical response may warrant dose adjustment.
Symptom Monitoring
- Skin rash (any type, especially blistering or widespread)
- Fever
- Swollen lymph nodes
- Facial swelling
- Sore throat
- Mouth sores
- Unusual bruising or bleeding
- Yellowing of skin or eyes (jaundice)
- Dark urine
- Severe fatigue
- Worsening depression or mood changes
- Thoughts of self-harm or suicide
- New or worsening seizures
- Dizziness
- Blurred or double vision
- Headache
- Nausea/vomiting
Special Patient Groups
Pregnancy
Lamotrigine crosses the placenta. While data suggest it may be associated with a slightly increased risk of oral clefts when used in the first trimester, overall risk is low and often outweighed by the benefits of seizure control. Close monitoring of lamotrigine levels is recommended during pregnancy as levels may decrease, requiring dose adjustments.
Trimester-Specific Risks:
First Trimester:
Slightly increased risk of oral clefts (e.g., cleft lip/palate) reported in some studies, though conflicting data exist. Risk is generally considered low. Folic acid supplementation is recommended for all women of childbearing potential taking AEDs.
Second Trimester:
Lamotrigine levels may decrease due to increased clearance, potentially leading to loss of seizure control. Therapeutic drug monitoring is often recommended.
Third Trimester:
Continued monitoring of levels. Levels may rapidly increase postpartum, requiring dose reduction to avoid toxicity.
Lactation
Lamotrigine is excreted into breast milk. While generally considered compatible with breastfeeding, infant monitoring for adverse effects (e.g., rash, sedation, poor feeding) is recommended. The amount transferred to the infant can be significant.
Infant Risk:
L3 (Moderate risk) - Monitor infant for rash, drowsiness, poor feeding, and weight gain. Consider therapeutic drug monitoring in the infant if concerns arise.
Pediatric Use
Higher risk of serious skin 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 highly dependent on concomitant medications.
Geriatric Use
Start with lower doses and titrate slowly, as elderly patients may have reduced renal or hepatic function and may be more sensitive to adverse effects. Monitor for dizziness and ataxia, which can increase fall risk.
Clinical Information
Clinical Pearls
- The most critical aspect of lamotrigine therapy is slow and careful dose titration to minimize the risk of serious skin rashes (SJS/TEN). Never accelerate the titration schedule.
- Patients must be educated to report any rash immediately and discontinue the medication unless advised otherwise by a healthcare professional.
- Significant drug interactions exist, particularly with valproate (requires lamotrigine dose reduction) and enzyme-inducing AEDs/oral contraceptives (require lamotrigine dose increase). Always review concomitant medications.
- Lamotrigine is effective for both focal and generalized seizures, and is a first-line agent for bipolar depression.
- Therapeutic drug monitoring (TDM) is not routinely required but can be very useful in specific situations (e.g., pregnancy, renal/hepatic impairment, suspected non-adherence, drug interactions, or lack of efficacy/toxicity at usual doses).
Alternative Therapies
- For Epilepsy: Levetiracetam, Carbamazepine, Oxcarbazepine, Valproate, Topiramate, Zonisamide, Gabapentin, Pregabalin.
- For Bipolar Disorder (Mood Stabilizers): Lithium, Valproate, Carbamazepine, Quetiapine, Olanzapine, Lurasidone, Cariprazine.
Cost & Coverage
Average Cost:
$30 - $150 per 30 tablets (100mg generic)
Generic Available:
Yes
Insurance Coverage:
Generic lamotrigine is typically covered as Tier 1 or Tier 2. Brand-name Lamictal may be Tier 3 or higher, requiring prior authorization.
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor promptly. To ensure your safety, never share your medication with others or take someone else's medication. When you receive this medication, you will also get a Medication Guide, which is a valuable resource that provides additional information. Please read this guide carefully and review it again whenever you refill your prescription. 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 crucial details, including the medication taken, the amount, and the time it occurred, to help healthcare professionals provide the best possible care.