Lamotrigine 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
Not available
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 stabilize mood in people with bipolar disorder. It works by calming overactive nerve signals in the brain.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your prescription 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. It's crucial to swallow the medication whole; do not chew, break, or crush it. If you have difficulty swallowing, discuss this with your doctor.
Important Safety Precautions
Do not change your dose or stop taking this medication without consulting your doctor, as this can 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 it, your doctor may recommend starting with a lower dose and gradually increasing it.
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.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. Instead, check with your pharmacist for guidance on the best disposal method or participate 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. 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 a missed one.
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your prescription 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. It's crucial to swallow the medication whole; do not chew, break, or crush it. If you have difficulty swallowing, discuss this with your doctor.
Important Safety Precautions
Do not change your dose or stop taking this medication without consulting your doctor, as this can 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 it, your doctor may recommend starting with a lower dose and gradually increasing it.
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.
When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. Instead, check with your pharmacist for guidance on the best disposal method or participate 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. 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 a 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 mood.
- Report any new skin rash immediately to your doctor, especially if it's severe, widespread, blistering, or accompanied by fever, swollen glands, or facial swelling.
- Avoid driving or operating machinery until you know how this medication affects you, as it can cause dizziness or blurred vision.
- Be aware that oral contraceptives can affect lamotrigine levels, and lamotrigine can affect oral contraceptive effectiveness. Discuss contraception with your doctor.
- Avoid alcohol or other CNS depressants, as they can increase side effects like dizziness and drowsiness.
- Carry a medical alert card or wear medical identification indicating you are taking lamotrigine, especially if you have epilepsy.
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:
Highly individualized due to slow titration required to minimize risk of serious rash. Typical maintenance doses for epilepsy range from 100-400 mg/day in 1-2 divided doses. For bipolar disorder maintenance, typical maintenance is 100-400 mg/day.
Condition-Specific Dosing:
Epilepsy (adjunctive, not on valproate or enzyme-inducing AEDs):
Initial 25 mg daily for 2 weeks, then 50 mg daily for 2 weeks, then increase by 50-100 mg/day every 1-2 weeks to maintenance.
Epilepsy (adjunctive, on valproate):
Initial 25 mg every other day for 2 weeks, then 25 mg daily for 2 weeks, then increase by 25-50 mg/day every 1-2 weeks to maintenance.
Epilepsy (adjunctive, on enzyme-inducing AEDs, not on valproate):
Initial 50 mg daily for 2 weeks, then 100 mg daily for 2 weeks, then increase by 100 mg/day every 1-2 weeks to maintenance.
Bipolar I Disorder (maintenance):
Initial 25 mg daily for 2 weeks, then 50 mg daily for 2 weeks, then 100 mg daily for 1 week, then 200 mg daily. Further increases up to 400 mg/day may be considered.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Dosing varies significantly by age, weight, and concomitant medications. Titration is crucial and often slower than adults. Consult specific guidelines for children 2 years and older.
Adolescent:
Dosing varies significantly by age, weight, and concomitant medications. Titration is crucial and often slower than adults. Consult specific guidelines.
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment required.
Moderate:
No specific dose adjustment required.
Severe:
Reduced maintenance doses may be effective for patients with significant renal impairment. Use with caution.
Dialysis:
Supplemental doses after dialysis are generally not required as only a small fraction is removed by hemodialysis. Use with caution and monitor clinical response.
Hepatic Impairment:
Mild:
No specific dose adjustment required.
Moderate:
Initial, escalation, and maintenance doses should be reduced by approximately 25%.
Severe:
Initial, escalation, and maintenance doses should be reduced by approximately 50%. Use with extreme caution.
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 is thought to prevent repetitive neuronal firing and reduce the propagation of seizure activity. It may also have effects on voltage-gated calcium channels and inhibit neuronal reuptake of serotonin.
Pharmacokinetics
Absorption:
Bioavailability:
98%
Tmax:
1.4-4.8 hours (oral)
FoodEffect:
Minimal effect on absorption rate or extent.
Distribution:
Vd:
0.9-1.3 L/kg
ProteinBinding:
Approximately 55%
CnssPenetration:
Yes
Elimination:
HalfLife:
25-33 hours (single dose, healthy adults; highly variable with concomitant medications)
Clearance:
Approximately 30 mL/min/kg (highly variable)
ExcretionRoute:
Renal (94% as metabolites, 2% unchanged drug)
Unchanged:
2%
Pharmacodynamics
OnsetOfAction:
Weeks (due to slow titration)
PeakEffect:
Weeks to months (upon reaching stable maintenance dose)
DurationOfAction:
24 hours (based on dosing frequency, but therapeutic effects are sustained with chronic use)
Safety & Warnings
BLACK BOX WARNING
Serious skin rashes requiring hospitalization and discontinuation of treatment have been reported, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The incidence of these rashes, which have resulted in death, is approximately 0.3% to 0.8% in pediatric patients (2 to 16 years of age) and 0.08% to 0.3% in adults. The risk of serious rash is increased by coadministration with valproate, exceeding the recommended initial dose, or exceeding the recommended dose escalation.
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 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 do not experience serious side effects, and many have only minor or no side effects at all. However, 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
Difficulty sleeping
Nose or throat irritation
Weight loss
Dry mouth
Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor 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 do not experience serious side effects, and many have only minor or no side effects at all. However, 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
Difficulty sleeping
Nose or throat irritation
Weight loss
Dry mouth
Back pain
Reporting Side Effects
If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- New or worsening skin rash (especially if severe, widespread, blistering, or accompanied by fever, swollen lymph nodes, facial swelling, or mouth sores)
- Fever, chills, sore throat, or other signs of infection
- Unusual bruising or bleeding
- Yellowing of the skin or eyes (jaundice)
- Severe fatigue or weakness
- Worsening seizures or new types of seizures
- Changes in mood or behavior, including new or worsening depression, anxiety, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, severe restlessness, hypomania, or mania
- Thoughts of self-harm or suicide
- Double vision or blurred vision
- Dizziness or unsteadiness
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, any of its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking dofetilide, as this may interact with the medication.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your complete medical history, including any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor to confirm 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, any of its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking dofetilide, as this may interact with the medication.
To ensure your safety, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your complete medical history, including any health problems you have
This information will help your doctor determine whether it is safe for you to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor to confirm 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 actions. Immediately contact your doctor if you experience new or worsening symptoms such as depression, nervousness, restlessness, irritability, panic attacks, or changes in mood or behavior. If suicidal thoughts or actions occur, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of a severe brain problem 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 packaging, consult with your pharmacist.
Heart Problems
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 certain 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 birth control methods 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 methods may be less effective in preventing pregnancy when taking this medication. Use alternative birth control methods, such as condoms, to prevent 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.
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 actions. Immediately contact your doctor if you experience new or worsening symptoms such as depression, nervousness, restlessness, irritability, panic attacks, or changes in mood or behavior. If suicidal thoughts or actions occur, seek medical attention right away.
Risk of Aseptic Meningitis
This medication may increase the risk of a severe brain problem 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 packaging, consult with your pharmacist.
Heart Problems
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 certain 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 birth control methods 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 methods may be less effective in preventing pregnancy when taking this medication. Use alternative birth control methods, such as condoms, to prevent 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.
Overdose Information
Overdose Symptoms:
- Nystagmus (involuntary eye movements)
- Ataxia (loss of coordination)
- Impaired consciousness
- Grand mal seizures
- Coma
- Intraventricular conduction delay (ECG changes)
- Cardiac arrest
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment is supportive; there is no specific antidote. Hemodialysis is not highly effective in removing lamotrigine.
Drug Interactions
Major Interactions
- Valproate (valproic acid, divalproex sodium): Significantly increases lamotrigine levels (up to 2-fold) by inhibiting glucuronidation, increasing risk of serious rash. Requires significant lamotrigine dose reduction.
- Oral Contraceptives (containing estrogen): Can significantly decrease lamotrigine levels (up to 50%) by inducing glucuronidation, potentially leading to loss of seizure control or mood stabilization. Requires lamotrigine dose increase.
- Enzyme-inducing Antiepileptic Drugs (e.g., carbamazepine, phenytoin, phenobarbital, primidone): Significantly decrease lamotrigine levels (up to 40-50%) by inducing glucuronidation. Requires lamotrigine dose increase.
Moderate Interactions
- Rifampin: Decreases lamotrigine levels.
- Lopinavir/Ritonavir: Decreases lamotrigine levels.
- Atazanavir/Ritonavir: Decreases lamotrigine levels.
- Risperidone: Lamotrigine may increase risperidone levels.
- Paracetamol (acetaminophen): May slightly decrease lamotrigine levels with chronic high-dose use.
Monitoring
Baseline Monitoring
Complete Blood Count (CBC) with differential
Rationale: To establish baseline and monitor for rare but serious hematologic abnormalities (e.g., neutropenia, aplastic anemia).
Timing: Prior to initiation
Liver Function Tests (LFTs)
Rationale: To establish baseline and monitor for rare 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 and educate patient on rash recognition.
Timing: Prior to initiation
Routine Monitoring
Clinical assessment for rash
Frequency: Daily during titration, then regularly
Target: Absence of new rash
Action Threshold: Any new rash, especially if accompanied by fever, lymphadenopathy, or facial swelling, requires immediate discontinuation and medical evaluation.
Seizure frequency/severity (if for epilepsy)
Frequency: Regularly (e.g., monthly initially, then every 3-6 months)
Target: Reduction in seizure frequency/severity
Action Threshold: Worsening seizures or inadequate control may indicate need for dose adjustment or re-evaluation.
Mood stability (if for bipolar disorder)
Frequency: Regularly (e.g., monthly initially, then every 3-6 months)
Target: Stabilization of mood, reduction in mood episodes
Action Threshold: Worsening mood symptoms (mania, depression) or inadequate control may indicate need for dose adjustment or re-evaluation.
Signs/symptoms of hypersensitivity reaction (fever, lymphadenopathy, facial edema, blood dyscrasias)
Frequency: Regularly, especially during titration
Target: Absence of symptoms
Action Threshold: Any new systemic symptoms require immediate discontinuation and medical evaluation.
Suicidal ideation/behavior
Frequency: Regularly, especially during initial therapy or dose changes
Target: Absence of suicidal thoughts or behaviors
Action Threshold: Any new or worsening suicidal thoughts or behaviors require immediate clinical assessment and intervention.
Therapeutic Drug Monitoring (TDM)
Frequency: Not routinely recommended, but can be useful in specific situations (e.g., suspected non-adherence, drug interactions, pregnancy, renal/hepatic impairment, suspected toxicity, or lack of efficacy)
Target: Generally 3-14 mcg/mL (for epilepsy), but clinical response is primary guide.
Action Threshold: Levels outside target range, especially if correlated with clinical symptoms or lack of efficacy, may warrant dose adjustment.
Symptom Monitoring
- New skin rash (especially if severe, widespread, blistering, or accompanied by fever)
- 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 seizures
- Changes in mood or behavior (e.g., new or worsening depression, anxiety, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, severe restlessness, hypomania, mania)
- Suicidal thoughts or attempts
- Vision changes (e.g., double vision, blurred vision)
- Dizziness or unsteadiness
Special Patient Groups
Pregnancy
Lamotrigine is often considered a preferred antiepileptic drug during pregnancy due to a lower risk of major congenital malformations compared to some other AEDs. However, its clearance can significantly increase during pregnancy, potentially leading to subtherapeutic levels and breakthrough seizures. Close monitoring of lamotrigine levels and dose adjustments may be necessary. Folic acid supplementation is recommended for all women of childbearing potential on AEDs.
Trimester-Specific Risks:
First Trimester:
Small, but debated, increased risk of oral clefts (e.g., cleft lip/palate). Overall risk of major congenital malformations appears to be low compared to other AEDs.
Second Trimester:
Increased lamotrigine clearance may occur, potentially requiring dose increases to maintain therapeutic levels and prevent seizure recurrence.
Third Trimester:
Continued increased clearance may necessitate further dose adjustments. Monitor for potential withdrawal symptoms in the neonate if maternal dose is high at delivery, though this is rare.
Lactation
Lamotrigine is excreted into breast milk. While generally considered compatible with breastfeeding, infants should be monitored for potential adverse effects such as rash, drowsiness, poor feeding, or poor weight gain. The benefits of breastfeeding should be weighed against the potential risks.
Infant Risk:
Low to moderate. Most exposed infants show no adverse effects. Rare reports of rash, drowsiness, or poor weight gain.
Pediatric Use
Lamotrigine is approved for use in pediatric patients 2 years and older for certain seizure types. The risk of serious rash is higher in pediatric patients (0.3% to 0.8%) compared to adults. Slow titration is even more critical in this population. Dosing is weight-based and highly dependent on concomitant medications.
Geriatric Use
Use with caution in elderly patients. Start with lower doses and titrate more slowly, as elderly patients may be more sensitive to the effects of lamotrigine and may have age-related decreases in renal or hepatic function. Monitor for adverse effects such as dizziness, ataxia, and rash.
Clinical Information
Clinical Pearls
- The most critical aspect of lamotrigine therapy is the slow titration schedule to minimize the risk of serious skin rash (SJS/TEN). Patients must be educated on this.
- Concomitant medications, especially valproate and enzyme-inducing AEDs (carbamazepine, phenytoin), significantly alter lamotrigine levels and require specific dose adjustments.
- Oral contraceptives can also significantly reduce lamotrigine levels, potentially leading to loss of efficacy. Patients should be counseled on this interaction.
- Any new rash, especially if accompanied by systemic symptoms (fever, lymphadenopathy, facial swelling), requires immediate discontinuation of lamotrigine and medical evaluation.
- Lamotrigine is generally less sedating and has fewer cognitive side effects than many other AEDs, making it a good choice for patients where these are concerns.
- While TDM is not routinely recommended, it can be very useful in specific situations like pregnancy, suspected non-adherence, or complex drug interactions.
Alternative Therapies
- For Epilepsy: Levetiracetam, Carbamazepine, Oxcarbazepine, Phenytoin, Valproate, Topiramate, Zonisamide, Gabapentin, Pregabalin, Lacosamide, Rufinamide, Clobazam, Perampanel, Cannabidiol.
- For Bipolar Disorder (maintenance): Lithium, Valproate, Quetiapine, Olanzapine, Aripiprazole, Cariprazine, Lurasidone.
Cost & Coverage
Average Cost:
Varies widely, typically $10-$100+ 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 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, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount consumed, and the time it occurred. This information will help healthcare professionals provide you with the most effective treatment.
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, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount consumed, and the time it occurred. This information will help healthcare professionals provide you with the most effective treatment.