LAMICTAL XR lamotrigine 25 mg Tablet, Film Coated, Extended Release, 30-count
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Mood Stabilizer class.
Where does this data come from?
🏭 Manufacturer & labeler
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🩺 Clinical
- I completely understand the impatience — but the slow ramp-up is one of the most important safety steps with lamotrigine. Going too fast significantly raises your risk of a serious...
- Why does my doctor keep telling me to increase my dose so slowly? Can't we just get to the right dose faster?
- That's a fair question, and the honest answer is: with lamotrigine, we can't reliably tell in advance which rashes are harmless and which are dangerous. So the rule is — call your...
- What kind of rash should I worry about? I get skin reactions from all sorts of things.
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Lamotrigine — tap one for details:
Lamotrigine may be associated with lower levels of 1 nutrient — worth a chat with your pharmacist, not a cause for alarm.
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
💊 What it looks like
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII EX438O2MRT
Ferric oxide yellow is a naturally occurring iron compound used as a colorant in medications. It gives tablets, capsules, and other forms a yellow or golden hue for identification and appearance.
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UNII 230OU9XXE4
A waxy substance made from glycerin and stearic acid that acts as an emulsifier to blend oily and watery ingredients together. It also helps thicken and stabilize the medicine's texture.
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Hypromellose is a plant-based thickener made from cellulose. It's used in medicines as a binder to hold ingredients together, a coating for tablets, and a thickener for liquids.
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Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII 1CS02G8656
Methacrylic acid is a synthetic polymer used as a coating material and binder in tablets and capsules. It helps control how and where the medication releases in the digestive system.
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UNII B697894SGQ
Polyethylene glycol 400 is a clear, thick liquid made from petroleum-derived polymers. It acts as a solvent and humectant in medicines, helping dissolve active ingredients and retain moisture in the formulation.
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UNII 6OZP39ZG8H
Polysorbate 80 is a synthetic emulsifier derived from sorbitol and oleic acid. It helps mix oil and water-based ingredients together in medications and improves how the product disperses in the body.
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UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
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UNII 15FIX9V2JP
Titanium dioxide is a bright white mineral powder commonly used as a colorant and opacifying agent. It makes pills and tablets white or lighter in color and helps make coatings non-transparent.
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UNII 8Z96QXD6UM
Triethyl citrate is a clear liquid derived from citric acid. It acts as a plasticizer and solvent in tablet coatings and film formulations, helping the coating remain flexible and adhere properly to the medicine.
11 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
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Can inactive ingredients matter?
💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per ea | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | $14.204 | $426.13 / 30 tablets |
| Medicaid paysCMS SDUD · 12 mo | $13.73 | $411.80 / 30 tablets |
| Medicare drug plans payPart D · Q2 2026 | $17.53 | $525.91 / 30 tablets |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Lamotrigine 25 mg 00228-1410-03 | Actavis | 30 tablets | $0.254 | AB | Discontinued | save 98% |
| Lamotrigine 25 mg 16714-0623-01 | NorthStar | 30 tablets | $0.254 | AB | Availability likely | save 98% |
| lamotrigine 25 mg 31722-0240-30 | Camber | 30 tablets | $0.254 | AB | Availability likely | save 98% |
| Lamotrigine 25 mg 65162-0949-03 | Amneal | 30 tablets | $0.254 | AB | Availability likely | save 98% |
| Lamictal Xr 25 mgthis 00173-0754-00 | GlaxoSmithKline | 30 tablets | $14.204 | AB | Availability likely | — |
| Lamotrigine 25 mg 13668-0339-01 | Torrent | 100 tablets | — | AB | FDA listed | — |
| Lamotrigine 25 mg 42291-0443-30 | AvKARE | 30 tablets | — | AB | FDA listed | — |
| Lamotrigine Extended Release 25 mg 49884-0561-01 | Par | 100 tablets | — | — | Discontinued | — |
| Lamotrigine 25 mg 55111-0717-05 | Dr.Reddy's | 500 tablets | — | AB | FDA listed | — |
| Lamotrigine 25 mg 68382-0979-05 | Zydus | 500 tablets | — | AB | FDA listed | — |
| lamotrigine 25 mg 69117-0044-01 | Yiling | 30 tablets | — | AB | FDA listed | — |
| Lamotrigine 25 mg 70771-1514-03 | Zydus | 30 tablets | — | AB | FDA listed | — |
| Lamotrigine 25 mg 71335-1469-01 | Bryant | 30 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available — see Therapeutic equivalents.
Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.
🛈 What do these terms mean?
- Patent
- Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
- Substance patent
- Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
- Formulation (product) patent
- Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
- Method-of-use patent
- A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
- Skinny label
- A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
- Exclusivity
- FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
- Paragraph IV
- A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
- RLD / RS
- Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
- TE / AB rating
- FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
- LOE (loss of exclusivity)
- The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.
Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.
| Patent | Type | Use code | Expires |
|---|---|---|---|
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
| US 8637512 ↗ | Drug product | — | Jan 7, 2029 |
Is there a generic version of LAMICTAL XR 25 MG TABLET?
The FDA approved a generic — why can’t I get it at my pharmacy yet?
Why do different websites show different generic release dates?
What does “FDA listed” mean?
What does a patent or protection date mean here?
What does “current Orange Book estimate” mean?
Can a generic come out before the last patent expires?
Can a generic come out after the listed dates?
What is the difference between patents and exclusivity?
Why are there multiple patent dates?
Where does this data come from?
🗺️ Medicaid utilization & spend
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
Where does this data come from?
📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 00173-0754-00 You're viewing this | 30 TABLET, FILM COATED, EXTENDED RELEASE in 1 BOTTLE (0173-0754-00) | 2009-07-06 | Active |
📄 Full prescribing information FDA SPL
🚨 Boxed Warning ▾
WARNING: SERIOUS SKIN RASHES LAMICTAL XR can cause serious rashes requiring hospitalization and discontinuation of treatment. The incidence of these rashes, which have included Stevens-Johnson syndrome, is approximately 0.8% (8 per 1,000) in pediatric patients (aged 2 to 16 years) receiving immediate-release lamotrigine as adjunctive therapy for epilepsy and 0.3% (3 per 1,000) in adults on adjunctive therapy for epilepsy. In a prospectively followed cohort of 1,983 pediatric patients (aged 2 to 16 years) with epilepsy taking adjunctive immediate release lamotrigine, there was 1 rash-related death.
LAMICTAL XR is not approved for patients younger than 13 years. In worldwide postmarketing experience, rare cases of toxic epidermal necrolysis and/or rash-related death have been reported in adult and pediatric patients, but their numbers are too few to permit a precise estimate of the rate. The risk of serious rash caused by treatment with LAMICTAL XR is not expected to differ from that with immediate-release lamotrigine.
However, the relatively limited treatment experience with LAMICTAL XR makes it difficult to characterize the frequency and risk of serious rashes caused by treatment with LAMICTAL XR. In addition to age, factors that may increase the risk of occurrence or the severity of rash caused by LAMICTAL XR include (1) coadministration of LAMICTAL XR with valproate (includes valproic acid and divalproex sodium), (2) exceeding the recommended initial dose of LAMICTAL XR, (3) exceeding the recommended dose escalation for LAMICTAL XR. , or (4) the presence of the HLA-B*1502 allele.
However, cases have occurred in the absence of these factors. Nearly all cases of life-threatening rashes caused by immediate-release lamotrigine have occurred within 2 to 8 weeks of treatment initiation. However, isolated cases have occurred after prolonged treatment (e.g., 6 months).
Accordingly, duration of therapy cannot be relied upon as means to predict the potential risk heralded by the first appearance of a rash. Although benign rashes are also caused by LAMICTAL XR, it is not possible to predict reliably which rashes will prove to be serious or life threatening. Accordingly, LAMICTAL XR 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 [see Warnings and Precautions ( 5.1 )] . WARNING: SERIOUS SKIN RASHES See full prescribing information for complete boxed warning. • Cases of life-threatening serious rashes, including Stevens-Johnson syndrome and toxic epidermal necrolysis, and/or rash-related death have been caused by lamotrigine. The rate of serious rash is greater in pediatric patients than in adults.
Additional factors that may increase the risk of rash include: • coadministration with valproate. • exceeding recommended initial dose of LAMICTAL XR. • exceeding recommended dose escalation for LAMICTAL XR. • presence of the HLA-B*1502 allele. ( 5.1 ) • Benign rashes are also caused by lamotrigine; however, it is not possible to predict which rashes will prove to be serious or life threatening. LAMICTAL XR should be discontinued at the first sign of rash, unless the rash is clearly not drug related.
( 5.1 )
🎯 Indications and Usage ▾
1 INDICATIONS AND USAGE LAMICTAL XR is indicated for: • adjunctive therapy for primary generalized tonic-clonic seizures (PGTC) and partial-onset seizures with or without secondary generalization in patients aged 13 years and older. ( 1.1 ) • conversion to monotherapy in patients aged 13 years and older with partial-onset seizures who are receiving treatment with a single antiepileptic drug (AED). ( 1.2 ) Limitation of use: Safety and effectiveness in patients younger than 13 years have not been established.
( 1.3 )
1.1Adjunctive Therapy LAMICTAL XR is indicated as adjunctive therapy for primary generalized tonic-clonic (PGTC) seizures and partial-onset seizures with or without secondary generalization in patients aged 13 years and older.
1.2Monotherapy LAMICTAL XR is indicated for conversion to monotherapy in patients aged 13 years and older with partial-onset seizures who are receiving treatment with a single antiepileptic drug (AED). Safety and effectiveness of LAMICTAL XR have not been established (1) as initial monotherapy or (2) for simultaneous conversion to monotherapy from 2 or more concomitant AEDs.
1.3Limitation of Use Safety and effectiveness of LAMICTAL XR for use in patients younger than 13 years have not been established.
⏱️ Dosage and Administration ▾
2 DOSAGE AND ADMINISTRATION LAMICTAL XR extended-release tablets are taken once daily, with or without food. Tablets must be swallowed whole and must not be chewed, crushed, or divided. • Do not exceed the recommended initial dosage and subsequent dose escalation. ( 2.1 ) • Initiation of adjunctive therapy and conversion to monotherapy requires slow titration dependent on concomitant AEDs; the prescriber must refer to the appropriate algorithm in Dosage and Administration.
( 2.2 , 2.3 ) • Adjunctive therapy: Target therapeutic dosage range is 200 to 600 mg daily and is dependent on concomitant AEDs. ( 2.2 ) • Conversion to monotherapy: Target therapeutic dosage range is 250 to 300 mg daily. ( 2.3 ) • Conversion from immediate-release lamotrigine to LAMICTAL XR: The initial dose of LAMICTAL XR should match the total daily dose of the immediate-release lamotrigine.
Patients should be closely monitored for seizure control after conversion. ( 2.4 ) • Do not restart LAMICTAL XR in patients who discontinued due to rash unless the potential benefits clearly outweigh the risks. ( 2.1 , 5.1 ) • Adjustments to maintenance doses will be necessary in most patients starting or stopping estrogen-containing products, including oral contraceptives.
( 2.1 , 5.9 ) • Discontinuation: Taper over a period of at least 2 weeks (approximately 50% dose reduction per week). ( 2.1 , 5.10 )
2.1General Dosing Considerations Rash There are suggestions that the risk of severe, potentially life-threatening rash may be increased by (1) coadministration of LAMICTAL XR with valproate, (2) exceeding the recommended initial dose of lamictal XR, or (3) exceeding the recommended dose escalation for lamictal XR. However, cases have occurred in the absence of these factors [see Boxed Warning ] . Therefore, it is important that the dosing recommendations be followed closely.
The risk of nonserious rash may be increased when the recommended initial dose and/or the rate of dose escalation for LAMICTAL XR is exceeded and in patients with a history of allergy or rash to other AEDs. LAMICTAL XR Patient Titration Kits provide LAMICTAL XR at doses consistent with the recommended titration schedule for the first 5 weeks of treatment, based upon concomitant medications, for patients with partial-onset seizures and are intended to help reduce the potential for rash. The use of LAMICTAL XR Patient Titration Kits is recommended for appropriate patients who are starting or restarting LAMICTAL XR [see How Supplied/Storage and Handling ( 16 )] .
It is recommended that LAMICTAL XR not be restarted in patients who discontinued due to rash associated with prior treatment with lamotrigine unless the potential benefits clearly outweigh the risks. If the decision is made to restart a patient who has discontinued LAMICTAL XR, the need to restart with the initial dosing recommendations should be assessed. The greater the interval of time since the previous dose, the greater consideration should be given to restarting with the initial dosing recommendations.
If a patient has discontinued lamotrigine for a period of more than 5 half-lives, it is recommended that initial dosing recommendations and guidelines be followed. The half-life of lamotrigine is affected by other concomitant medications [see Clinical Pharmacology ( 12.3 )] . LAMICTAL XR Added to Drugs Known to Induce or Inhibit Glucuronidation Because lamotrigine is metabolized predominantly by glucuronic acid conjugation, drugs that are known to induce or inhibit glucuronidation may affect the apparent clearance of lamotrigine.
Drugs that induce glucuronidation include carbamazepine, phenytoin, phenobarbital, primidone, rifampin, estrogen-containing products, including oral contraceptives, and the protease inhibitors lopinavir/ritonavir and atazanavir/ritonavir. Valproate inhibits glucuronidation. For dosing considerations for LAMICTAL XR in patients on estrogen-containing products including contraceptives and atazanavir/ritonavir, se…
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS AND STRENGTHS Extended-release tablets: 25 mg, 50 mg, 100 mg, 200 mg, 250 mg, and 300 mg. ( 3.1 , 16 )
3.1Extended-Release Tablets 25-mg, yellow with white center, round, biconvex, film-coated tablets printed with “LAMICTAL” and “XR 25.” 50-mg, green with white center, round, biconvex, film-coated tablets printed with “LAMICTAL” and “XR 50.” 100-mg, orange with white center, round, biconvex, film-coated tablets printed with “LAMICTAL” and “XR 100.” 200-mg, blue with white center, round, biconvex, film-coated tablets printed with “LAMICTAL” and “XR 200.” 250-mg, purple with white center, caplet-shaped, film-coated tablets printed with “LAMICTAL” and “XR 250.” 300-mg, gray with white center, caplet-shaped, film-coated tablets printed with “LAMICTAL” and “XR 300.”
⛔ Contraindications ▾
4 CONTRAINDICATIONS LAMICTAL XR is contraindicated in patients who have demonstrated hypersensitivity (e.g., rash, angioedema, acute urticaria, extensive pruritus, mucosal ulceration) to the drug or its ingredients [see Boxed Warning , Warnings and Precautions ( 5.1 , 5.3 )] . Hypersensitivity to the drug or its ingredients. ( Boxed Warning , 4 )
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS • Life-threatening serious rash and/or rash-related death: Discontinue at the first sign of rash, unless the rash is clearly not drug related. ( Boxed Warning , 5.1 ) • Hemophagocytic lymphohistiocytosis: Consider this diagnosis and evaluate patients immediately if they develop signs or symptoms of systemic inflammation. Discontinue LAMICTAL XR if an alternative etiology is not established.
( 5.2 ) • Fatal or life-threatening hypersensitivity reaction: Multiorgan hypersensitivity reactions, also known as drug reaction with eosinophilia and systemic symptoms (DRESS), may be fatal or life threatening. Early signs may include rash, fever, and lymphadenopathy. These reactions may be associated with other organ involvement, such as hepatitis, hepatic failure, blood dyscrasias, or acute multiorgan failure.
LAMICTAL XR should be discontinued if alternate etiology for this reaction is not found. ( 5.3 ) • Cardiac rhythm and conduction abnormalities: Based on in vitro findings, LAMICTAL XR could cause serious arrhythmias and/or death in patients with certain underlying cardiac disorders or arrhythmias. Any expected or observed benefit of LAMICTAL XR in an individual patient with clinically important structural or functional heart disease must be carefully weighed against the risk for serious arrythmias and/or death for that patient.
( 5.4 ) • Blood dyscrasias (e.g., neutropenia, thrombocytopenia, pancytopenia): May occur, either with or without an associated hypersensitivity syndrome. Monitor for signs of anemia, unexpected infection, or bleeding. ( 5.5 ) • Suicidal behavior and ideation: Monitor for suicidal thoughts or behaviors.
( 5.6 ) • Aseptic meningitis: Monitor for signs of meningitis. ( 5.7 ) • Medication errors due to product name confusion: Strongly advise patients to visually inspect tablets to verify the received drug is correct. ( 5.8 , 16 , 17 )
5.1Serious Skin Rashes [see Boxed Warning] The risk of serious rash caused by treatment with LAMICTAL XR is not expected to differ from that with immediate-release lamotrigine [see Boxed Warning ] . However, the relatively limited treatment experience with LAMICTAL XR makes it difficult to characterize the frequency and risk of serious rashes caused by treatment with LAMICTAL XR. Pediatric Population The incidence of serious rash associated with hospitalization and discontinuation of immediate-release lamotrigine in a prospectively followed cohort of pediatric patients (aged 2 to 16 years) with epilepsy receiving adjunctive therapy with immediate-release lamotrigine was approximately 0.8% (16 of 1,983).
When 14 of these cases were reviewed by 3 expert dermatologists, there was considerable disagreement as to their proper classification. To illustrate, 1 dermatologist considered none of the cases to be Stevens-Johnson syndrome; another assigned 7 of the 14 to this diagnosis. There was 1 rash-related death in this 1,983-patient cohort.
Additionally, there have been rare cases of toxic epidermal necrolysis with and without permanent sequelae and/or death in U.S. and foreign postmarketing experience. There is evidence that the inclusion of valproate in a multidrug regimen increases the risk of serious, potentially life-threatening rash in pediatric patients. In pediatric patients who used valproate concomitantly, 1.2% (6 of 482) experienced a serious rash compared with 0.6% (6 of 952) patients not taking valproate.
LAMICTAL XR is not approved in patients younger than 13 years. Adult Population Serious rash associated with hospitalization and discontinuation of immediate-release lamotrigine occurred in 0.3% (11 of 3,348) of adult patients who received immediate-release lamotrigine in premarketing clinical trials of epilepsy. In worldwide postmarketing experience, rare cases of rash-related death have been reported, but their numbers are too few to permit a precise estimate of the rate.
Among the rashes leading to hospitalization were Stevens-Johnson syndrom…
🤒 Adverse Reactions ▾
6 ADVERSE REACTIONS The following serious adverse reactions are described in more detail in the Warnings and Precautions section of the labeling: • Serious Skin Rashes [see Warnings and Precautions ( 5.1 )] • Hemophagocytic Lymphohistiocytosis [see Warnings and Precautions ( 5.2 )] • Multiorgan Hypersensitivity Reactions and Organ Failure [see Warnings and Precautions ( 5.3 )] • Cardiac Rhythm and Conduction Abnormalities [see Warnings and Precautions ( 5.4 )] • Blood Dyscrasias [see Warnings and Precautions ( 5.5 )] • Suicidal Behavior and Ideation [see Warnings and Precautions ( 5.6 )] • Aseptic Meningitis [see Warnings and Precautions ( 5.7 )] • Withdrawal Seizures [see Warnings and Precautions ( 5.10 )] • Status Epilepticus [see Warnings and Precautions ( 5.11 )] • Most common adverse reactions with use as adjunctive therapy (treatment difference between LAMICTAL XR and placebo ≥4%) were dizziness, tremor/intention tremor, vomiting, and diplopia.
( 6.1 ) • Most common adverse reactions with use as monotherapy were similar to those seen with previous trials conducted with immediate-release lamotrigine and LAMICTAL XR. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact GlaxoSmithKline at 1-888-825-5249 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .
6.1Clinical Trial Experience with LAMICTAL XR for Treatment of Primary Generalized Tonic-Clonic and Partial-Onset Seizures Most Common Adverse Reactions in Clinical Trials Adjunctive Therapy in Patients with Epilepsy: Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. In these 2 trials, adverse reactions led to withdrawal of 4 (2%) patients in the group receiving placebo and 10 (5%) patients in the group receiving LAMICTAL XR.
Dizziness was the most common reason for withdrawal in the group receiving LAMICTAL XR (5 patients [3%]). The next most common adverse reactions leading to withdrawal in 2 patients each (1%) were rash, headache, nausea, and nystagmus. Table 4 displays the incidence of adverse reactions in these two 19-week, double-blind, placebo-controlled trials of patients with PGTC and partial onset seizures.
Table 4. Adverse Reactions in Pooled, Placebo-Controlled, Adjunctive Trials in Patients with Epilepsy a a Adverse reactions that occurred in at least 2% of patients treated with LAMICTAL XR and at a greater incidence than placebo. Body System/ Adverse Reaction Percent of Patients Receiving Adjunctive LAMICTAL XR (n = 190) Percent of Patients Receiving Adjunctive Placebo (n = 195) Ear and labyrinth disorders Vertigo 3 <1 Eye disorders Diplopia 5 <1 Vision blurred 3 2 Gastrointestinal disorders Nausea 7 4 Vomiting 6 3 Diarrhea 5 3 Constipation 2 <1 Dry mouth 2 1 General disorders and administration site conditions Asthenia and fatigue 6 4 Infections and infestations Sinusitis 2 1 Metabolic and nutritional disorders Anorexia 3 2 Musculoskeletal and connective tissue disorder Myalgia 2 0 Nervous system Dizziness 14 6 Tremor and intention tremor 6 1 Somnolence 5 3 Cerebellar coordination and balance disorder 3 0 Nystagmus 2 <1 Psychiatric disorders Depression 3 <1 Anxiety 3 0 Respiratory, thoracic, and mediastinal disorders Pharyngolaryngeal pain 3 2 Vascular disorder Hot flush 2 0 Note: In these trials the incidence of nonserious rash was 2% for LAMICTAL XR and 3% for placebo.
In clinical trials evaluating immediate-release lamotrigine, the rate of serious rash was 0.3% in adults on adjunctive therapy for epilepsy [see Boxed Warning ] . Adverse reactions were also analyzed to assess the incidence of the onset of an event in the titration period, and in the maintenance period, and if adverse reactions occurring in the titration phase persisted in the maintenance phase. The incidence for many adverse reactions caused by treatment with LAMICTAL XR was in…
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS Significant drug interactions with lamotrigine are summarized in this section. Additional details of these drug interaction studies, which were conducted using immediate-release lamotrigine, are provided in the Clinical Pharmacology section [see Clinical Pharmacology ( 12.3 )] . Uridine 5´-diphospho-glucuronyl transferases (UGT) have been identified as the enzymes responsible for metabolism of lamotrigine.
Drugs that induce or inhibit glucuronidation may, therefore, affect the apparent clearance of lamotrigine. Strong or moderate inducers of the cytochrome P450 3A4 (CYP3A4) enzyme, which are also known to induce UGT, may also enhance the metabolism of lamotrigine. Those drugs that have been demonstrated to have a clinically significant impact on lamotrigine metabolism are outlined in Table 13.
Specific dosing guidance for these drugs is provided in the Dosage and Administration section, and, for women taking estrogen-containing products, including oral contraceptives, in the Warnings and Precautions section [see Dosage and Administration ( 2.1 ), Warnings and Precautions, ( 5.9 )] . Table 5. Established and Other Potentially Significant Drug Interactions ↓ = Decreased (induces lamotrigine glucuronidation). ↑ = Increased (inhibits lamotrigine glucuronidation). ? = Conflicting data.
Concomitant Drug Effect on Concentration of Lamotrigine or Concomitant Drug Clinical Comment Estrogen-containing oral contraceptive preparations containing 30 mcg ethinylestradiol and 150 mcg levonorgestrel ↓ lamotrigine Decreased lamotrigine concentrations approximately 50%. ↓ levonorgestrel Decrease in levonorgestrel component by 19%. Carbamazepine and carbamazepine epoxide ↓ lamotrigine Addition of carbamazepine decreases lamotrigine concentration approximately 40%. ? carbamazepine epoxide May increase carbamazepine epoxide levels.
Lopinavir/ritonavir ↓ lamotrigine Decreased lamotrigine concentration approximately 50%. Atazanavir/ritonavir ↓ lamotrigine Decreased lamotrigine AUC approximately 32%. Phenobarbital/primidone ↓ lamotrigine Decreased lamotrigine concentration approximately 40%.
Phenytoin ↓ lamotrigine Decreased lamotrigine concentration approximately 40%. Rifampin ↓ lamotrigine Decreased lamotrigine AUC approximately 40%. Valproate ↑ lamotrigine Increased lamotrigine concentrations slightly more than 2-fold. ? valproate There are conflicting study results regarding effect of lamotrigine on valproate concentrations: 1) a mean 25% decrease in valproate concentrations in healthy volunteers, 2) no change in valproate concentrations in controlled clinical trials in patients with epilepsy.
Effect of LAMICTAL XR on Organic Cationic Transporter 2 Substrates Lamotrigine is an inhibitor of renal tubular secretion via organic cationic transporter 2 (OCT2) proteins [see Clinical Pharmacology ( 12.3 )] . This may result in increased plasma levels of certain drugs that are substantially excreted via this route. Coadministration of LAMICTAL XR with OCT2 substrates with a narrow therapeutic index (e.g., dofetilide) is not recommended. • Valproate increases lamotrigine concentrations more than 2-fold.
( 7 , 12.3 ) • Carbamazepine, phenytoin, phenobarbital, primidone, and rifampin decrease lamotrigine concentrations by approximately 40%. ( 7 , 12.3 ) • Estrogen-containing oral contraceptives decrease lamotrigine concentrations by approximately 50%. ( 7 , 12.3 ) • Protease inhibitors lopinavir/ritonavir and atazanavir/lopinavir decrease lamotrigine exposure by approximately 50% and 32%, respectively.
( 7 , 12.3 ) • Coadministration with organic cationic transporter 2 (OCT2) substrates with narrow therapeutic index is not recommended ( 7 , 12.3 )
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS • Pregnancy: Based on animal data may cause fetal harm. ( 8.1 ) • Hepatic impairment: Dosage adjustments required in patients with moderate and severe liver impairment. ( 2.1 , 8.6 ) • Renal impairment: Reduced maintenance doses may be effective for patients with significant renal impairment. ( 2.1 , 8.7 )
8.1Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, including LAMICTAL XR, during pregnancy. Encourage women who are taking LAMICTAL XR during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling 1-888-233-2334 or visiting http://www.aedpregnancyregistry.org/. Risk Summary Data from several prospective pregnancy exposure registries and epidemiological studies of pregnant women have not detected an increased frequency of major congenital malformations or a consistent pattern of malformations among women exposed to lamotrigine compared with the general population (see Data) .
In animal studies, administration of lamotrigine during pregnancy resulted in developmental toxicity (increased mortality, decreased body weight, increased structural variation, neurobehavioral abnormalities) at doses lower than those administered clinically. Lamotrigine decreased fetal folate concentrations in rats, an effect known to be associated with adverse pregnancy outcomes in animals and humans (see Data) . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Clinical Considerations Disease-associated Maternal and/or Embryofetal Risk Epilepsy, with or without exposure to antiepileptic drugs, has been associated with several adverse outcomes during pregnancy, including preeclampsia, preterm labor, antepartum and postpartum hemorrhage, placental abruption, poor fetal growth, prematurity, fetal death, and maternal mortality. The risk of maternal or fetal injury may be greatest for patients with untreated or poorly controlled convulsive seizures. Women with epilepsy who become pregnant should not abruptly discontinue antiepileptic drugs, including LAMICTAL XR, due to the risk of status epilepticus or severe seizures, which may be life-threatening [see Warnings and Precautions ( 5.10 )].
Dose Adjustments During Pregnancy and the Postpartum Period As with other AEDs, physiological changes during pregnancy may affect lamotrigine concentrations and/or therapeutic effect. There have been reports of decreased lamotrigine concentrations during pregnancy and restoration of pre-pregnancy concentrations after delivery. Dose adjustments may be necessary to maintain clinical response.
Data Human Data: Data from several international pregnancy registries have not shown an increased risk for malformations overall. The International Lamotrigine Pregnancy Registry reported major congenital malformations in 2.2% (95% CI: 1.6%, 3.1%) of 1,558 infants exposed to lamotrigine monotherapy in the first trimester of pregnancy. The NAAED Pregnancy Registry reported major congenital malformations among 2.0% of 1,562 infants exposed to lamotrigine monotherapy in the first trimester.
EURAP, a large international pregnancy registry focused outside of North America, reported major birth defects in 2.9% (95% CI: 2.3%, 3.7%) of 2,514 exposures to lamotrigine monotherapy in the first trimester. The frequency of major congenital malformations was similar to estimates from the general population. The NAAED Pregnancy Registry observed an increased risk of isolated oral clefts: among 2,200 infants exposed to lamotrigine early in pregnancy, the risk of oral clefts was 3.2 per 1,000 (95% CI: 1.4, 6.3), a 3-fold increased risk versus unexposed healthy controls.
This finding has not been observed in other large international pregnancy registries. Furthermore, a case-control study based on 21 congenital ano…
🤰 Pregnancy ▾
8.1Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, including LAMICTAL XR, during pregnancy. Encourage women who are taking LAMICTAL XR during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling 1-888-233-2334 or visiting http://www.aedpregnancyregistry.org/. Risk Summary Data from several prospective pregnancy exposure registries and epidemiological studies of pregnant women have not detected an increased frequency of major congenital malformations or a consistent pattern of malformations among women exposed to lamotrigine compared with the general population (see Data) .
In animal studies, administration of lamotrigine during pregnancy resulted in developmental toxicity (increased mortality, decreased body weight, increased structural variation, neurobehavioral abnormalities) at doses lower than those administered clinically. Lamotrigine decreased fetal folate concentrations in rats, an effect known to be associated with adverse pregnancy outcomes in animals and humans (see Data) . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Clinical Considerations Disease-associated Maternal and/or Embryofetal Risk Epilepsy, with or without exposure to antiepileptic drugs, has been associated with several adverse outcomes during pregnancy, including preeclampsia, preterm labor, antepartum and postpartum hemorrhage, placental abruption, poor fetal growth, prematurity, fetal death, and maternal mortality. The risk of maternal or fetal injury may be greatest for patients with untreated or poorly controlled convulsive seizures. Women with epilepsy who become pregnant should not abruptly discontinue antiepileptic drugs, including LAMICTAL XR, due to the risk of status epilepticus or severe seizures, which may be life-threatening [see Warnings and Precautions ( 5.10 )].
Dose Adjustments During Pregnancy and the Postpartum Period As with other AEDs, physiological changes during pregnancy may affect lamotrigine concentrations and/or therapeutic effect. There have been reports of decreased lamotrigine concentrations during pregnancy and restoration of pre-pregnancy concentrations after delivery. Dose adjustments may be necessary to maintain clinical response.
Data Human Data: Data from several international pregnancy registries have not shown an increased risk for malformations overall. The International Lamotrigine Pregnancy Registry reported major congenital malformations in 2.2% (95% CI: 1.6%, 3.1%) of 1,558 infants exposed to lamotrigine monotherapy in the first trimester of pregnancy. The NAAED Pregnancy Registry reported major congenital malformations among 2.0% of 1,562 infants exposed to lamotrigine monotherapy in the first trimester.
EURAP, a large international pregnancy registry focused outside of North America, reported major birth defects in 2.9% (95% CI: 2.3%, 3.7%) of 2,514 exposures to lamotrigine monotherapy in the first trimester. The frequency of major congenital malformations was similar to estimates from the general population. The NAAED Pregnancy Registry observed an increased risk of isolated oral clefts: among 2,200 infants exposed to lamotrigine early in pregnancy, the risk of oral clefts was 3.2 per 1,000 (95% CI: 1.4, 6.3), a 3-fold increased risk versus unexposed healthy controls.
This finding has not been observed in other large international pregnancy registries. Furthermore, a case-control study based on 21 congenital anomaly registries covering over 10 million births in Europe reported an adjusted odds ratio for isolated oral clefts with lamotrigine exposure of 1.45 (95% CI: 0.8, 2.63). Several meta-analyses have not reported an increased risk of major congenital malformations following lamotrigine exposure in pregnancy compared with healthy and diseas…
🧒 Pediatric Use ▾
8.4Pediatric Use LAMICTAL XR is indicated as adjunctive therapy for PGTC and partial-onset seizures with or without secondary generalization in patients aged 13 years and older. Safety and effectiveness of LAMICTAL XR for any use in patients younger than 13 years have not been established. Immediate-release lamotrigine is indicated as adjunctive therapy in patients aged 2 years and older for partial-onset seizures, the generalized seizures of Lennox-Gastaut syndrome, and PGTC seizures.
Safety and efficacy of immediate-release lamotrigine used as adjunctive treatment for partial-onset seizures were not demonstrated in a small, randomized, double-blind, placebo-controlled withdrawal trial in very young pediatric patients (aged 1 to 24 months). Immediate-release lamotrigine was associated with an increased risk for infectious adverse reactions (lamotrigine 37%, placebo 5%), and respiratory adverse reactions (lamotrigine 26%, placebo 5%). Infectious adverse reactions included bronchiolitis, bronchitis, ear infection, eye infection, otitis externa, pharyngitis, urinary tract infection, and viral infection.
Respiratory adverse reactions included nasal congestion, cough, and apnea. Juvenile Animal Data In a juvenile animal study in which lamotrigine (oral doses of 0, 5, 15, or 30 mg/kg) was administered to young rats from postnatal day 7 to 62, decreased viability and growth were seen at the highest dose tested and long-term neurobehavioral abnormalities (decreased locomotor activity, increased reactivity, and learning deficits in animals tested as adults) were observed at the 2 highest doses. The no-effect dose for adverse developmental effects in juvenile animals is less than the human dose of 400 mg/day on a mg/m 2 basis.
🧓 Geriatric Use ▾
8.5Geriatric Use Clinical trials of LAMICTAL XR for epilepsy did not include sufficient numbers of patients aged 65 years and older to determine whether they respond differently from younger patients or exhibit a different safety profile than that of younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy.
🆘 Overdosage ▾
10 OVERDOSAGE
10.1Human Overdose Experience Overdoses involving quantities up to 15 g have been reported for immediate-release lamotrigine, some of which have been fatal. Overdose has resulted in ataxia, nystagmus, seizures (including tonic-clonic seizures), decreased level of consciousness, coma, and intraventricular conduction delay.
10.2Management of Overdose There are no specific antidotes for lamotrigine. Following a suspected overdose, hospitalization of the patient is advised. General supportive care is indicated, including frequent monitoring of vital signs and close observation of the patient.
If indicated, emesis should be induced; usual precautions should be taken to protect the airway. It is uncertain whether hemodialysis is an effective means of removing lamotrigine from the blood. In 6 renal failure patients, about 20% of the amount of lamotrigine in the body was removed by hemodialysis during a 4-hour session.
A Poison Control Center should be contacted for information on the management of overdosage of LAMICTAL XR.
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown. In animal models designed to detect anticonvulsant activity, lamotrigine was effective in preventing seizure spread in the maximum electroshock (MES) and pentylenetetrazol (scMet) tests, and prevented seizures in the visually and electrically evoked after-discharge (EEAD) tests for antiepileptic activity. Lamotrigine also displayed inhibitory properties in the kindling model in rats both during kindling development and in the fully kindled state.
The relevance of these models to human epilepsy, however, is not known. One proposed mechanism of action of lamotrigine, the relevance of which remains to be established in humans, involves an effect on sodium channels. In vitro pharmacological studies suggest that lamotrigine inhibits voltage-sensitive sodium channels, thereby stabilizing neuronal membranes and consequently modulating presynaptic transmitter release of excitatory amino acids (e.g., glutamate and aspartate).
Effect of Lamotrigine on N-Methyl d-Aspartate-Receptor–Mediated Activity Lamotrigine did not inhibit N-methyl d-aspartate (NMDA)-induced depolarizations in rat cortical slices or NMDA-induced cyclic GMP formation in immature rat cerebellum, nor did lamotrigine displace compounds that are either competitive or noncompetitive ligands at this glutamate receptor complex (CNQX, CGS, TCHP). The IC 50 for lamotrigine effects on NMDA-induced currents (in the presence of 3 µM of glycine) in cultured hippocampal neurons exceeded 100 µM.
12.2Pharmacodynamics Folate Metabolism In vitro, lamotrigine inhibited dihydrofolate reductase, the enzyme that catalyzes the reduction of dihydrofolate to tetrahydrofolate. Inhibition of this enzyme may interfere with the biosynthesis of nucleic acids and proteins. When oral daily doses of lamotrigine were given to pregnant rats during organogenesis, fetal, placental, and maternal folate concentrations were reduced.
Significantly reduced concentrations of folate are associated with teratogenesis [see Use in Specific Populations ( 8.1 )] . Folate concentrations were also reduced in male rats given repeated oral doses of lamotrigine. Reduced concentrations were partially returned to normal when supplemented with folinic acid.
Cardiac Electrophysiology Effect of Lamotrigine: In vitro studies show that lamotrigine exhibits Class IB antiarrhythmic activity at therapeutically relevant concentrations. It inhibits human cardiac sodium channels with rapid onset and offset kinetics and strong voltage dependence, consistent with other Class IB antiarrhythmic agents. At therapeutic doses, LAMICTAL XR did not slow ventricular conduction (widen QRS) in healthy individuals in a thorough QT study; however, in patients with clinically important structural or functional heart disease or (i.e., patients with heart failure, valvular heart disease, congenital heart disease, conduction system disease, ventricular arrhythmias, cardiac channelopathies [e.g., Brugada syndrome], clinically important ischemic heart disease, or multiple risk factors for coronary artery disease), LAMICTAL XR could slow ventricular conduction (widen QRS) and induce proarrhythmia, which can lead to sudden death.
Elevated heart rates could also increase the risk of ventricular conduction slowing with LAMICTAL XR. Effect of Lamotrigine Metabolite: In dogs, lamotrigine is extensively metabolized to a 2-N-methyl metabolite. This metabolite causes dose-dependent prolongation of the PR interval, widening of the QRS complex, and, at higher doses, complete AV conduction block.
The in vitro electrophysiological effects of this metabolite have not been studied. Similar cardiovascular effects from this metabolite are not anticipated in humans because only trace amounts of the 2-N-methyl metabolite (<0.6% of lamotrigine dose) have been found in human urine [see Clinical Pharmacology ( 12.3 )] . However, it is…
🧬 Mechanism of Action ▾
12.1Mechanism of Action The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown. In animal models designed to detect anticonvulsant activity, lamotrigine was effective in preventing seizure spread in the maximum electroshock (MES) and pentylenetetrazol (scMet) tests, and prevented seizures in the visually and electrically evoked after-discharge (EEAD) tests for antiepileptic activity. Lamotrigine also displayed inhibitory properties in the kindling model in rats both during kindling development and in the fully kindled state.
The relevance of these models to human epilepsy, however, is not known. One proposed mechanism of action of lamotrigine, the relevance of which remains to be established in humans, involves an effect on sodium channels. In vitro pharmacological studies suggest that lamotrigine inhibits voltage-sensitive sodium channels, thereby stabilizing neuronal membranes and consequently modulating presynaptic transmitter release of excitatory amino acids (e.g., glutamate and aspartate).
Effect of Lamotrigine on N-Methyl d-Aspartate-Receptor–Mediated Activity Lamotrigine did not inhibit N-methyl d-aspartate (NMDA)-induced depolarizations in rat cortical slices or NMDA-induced cyclic GMP formation in immature rat cerebellum, nor did lamotrigine displace compounds that are either competitive or noncompetitive ligands at this glutamate receptor complex (CNQX, CGS, TCHP). The IC 50 for lamotrigine effects on NMDA-induced currents (in the presence of 3 µM of glycine) in cultured hippocampal neurons exceeded 100 µM.
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING LAMICTAL XR (lamotrigine) extended-release tablets 25-mg, yellow with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 25”, unit-of-use bottles of 30 with orange caps (NDC 0173-0754-00). 50-mg, green with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 50”, unit-of-use bottles of 30 with orange caps (NDC 0173-0755-00). 100-mg, orange with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 100”, unit-of-use bottles of 30 with orange caps (NDC 0173-0756-00).
200-mg, blue with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 200”, unit-of-use bottles of 30 with orange caps (NDC 0173-0757-00). 250-mg, purple with a white center, caplet-shaped, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 250”, unit-of-use bottles of 30 with orange caps (NDC 0173-0781-00). 300-mg, gray with a white center, caplet-shaped, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 300”, unit-of-use bottles of 30 with orange caps (NDC 0173-0761-00).
LAMICTAL XR (lamotrigine) Patient Titration Kit for Patients Taking Valproate (Blue XR Kit) 25-mg, yellow with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 25” and 50 mg, green with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 50”; blister pack of 21/25-mg tablets and 7/50-mg tablets (NDC 0173-0758-00). LAMICTAL XR (lamotrigine) Patient Titration Kit for Patients Taking Carbamazepine, Phenytoin, Phenobarbital, or Primidone, and Not Taking Valproate (Green XR Kit) 50-mg, green with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 50”; 100 mg, orange with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 100”; and 200 mg, blue with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 200”; blister pack of 14/50-mg tablets, 14/100-mg tablets, and 7/200-mg tablets (NDC 0173-0759-00).
LAMICTAL XR (lamotrigine) Patient Titration Kit for Patients Not Taking Carbamazepine, Phenytoin, Phenobarbital, Primidone, or Valproate (Orange XR Kit) 25-mg, yellow with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 25”; 50 mg, green with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 50”; and 100 mg, orange with a white center, round, biconvex, film-coated tablets printed on one face in black ink with “LAMICTAL” and “XR 100”; blister pack of 14/25-mg tablets, 14/50-mg tablets, and 7/100-mg tablets (NDC 0173-0760-00).
Storage Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature].
📋 Description ▾
11 DESCRIPTION LAMICTAL XR (lamotrigine), an AED of the phenyltriazine class, is chemically unrelated to existing AEDs. Lamotrigine’s chemical name is 3,5-diamino-6-(2,3-dichlorophenyl)- as -triazine, its molecular formula is C 9 H 7 N 5 Cl 2 , and its molecular weight is 256.09. Lamotrigine is a white to pale cream-colored powder and has a pK a of 5.7. Lamotrigine is very slightly soluble in water (0.17 mg/mL at 25°C) and slightly soluble in
0.1M HCl (4.1 mg/mL at 25°C). The structural formula is: LAMICTAL XR extended-release tablets are supplied for oral administration as 25-mg (yellow with white center), 50-mg (green with white center), 100-mg (orange with white center), 200-mg (blue with white center), 250-mg (purple with white center), and 300-mg (gray with white center) tablets. Each tablet contains the labeled amount of lamotrigine and the following inactive ingredients: glycerol monostearate, hypromellose, lactose monohydrate; magnesium stearate; methacrylic acid copolymer dispersion, polyethylene glycol 400, polysorbate 80, silicon dioxide (25- and 50-mg tablets only), titanium dioxide, triethyl citrate, carmine (250-mg tablet only), iron oxide black (50-, 250-, and 300-mg tablets only), iron oxide yellow (25-, 50-, and 100-mg tablets only), iron oxide red (100-mg tablet only), FD&C Blue No.
2 Aluminum Lake (200- and 250-mg tablets only). Tablets are printed with edible black ink. LAMICTAL XR extended-release tablets contain a modified-release eroding formulation as the core.
The tablets are coated with a clear enteric coat and have an aperture drilled through the coats on both faces of the tablet (DiffCORE) to enable a controlled release of drug in the acidic environment of the stomach. The combination of this and the modified-release core are designed to control the dissolution rate of lamotrigine over a period of approximately 12 to 15 hours, leading to a gradual increase in serum lamotrigine levels. Lamictal XR Chemical Structure
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Medication Guide). Rash Prior to initiation of treatment with LAMICTAL XR, inform patients that a rash or other signs or symptoms of hypersensitivity (e.g., fever, lymphadenopathy) may herald a serious medical event and instruct them to report any such occurrence to their healthcare providers immediately. Hemophagocytic Lymphohistiocytosis Prior to initiation of treatment with LAMICTAL XR, inform patients that excessive immune activation may occur with LAMICTAL XR and that they should report signs or symptoms such as fever, rash, or lymphadenopathy to a healthcare provider immediately.
Multiorgan Hypersensitivity Reactions, Blood Dyscrasias, and Organ Failure Inform patients that multiorgan hypersensitivity reactions and acute multiorgan failure may occur with LAMICTAL XR. Isolated organ failure or isolated blood dyscrasias without evidence of multiorgan hypersensitivity may also occur. Instruct patients to contact their healthcare providers immediately if they experience any signs or symptoms of these conditions [see Warnings and Precautions ( 5.3 , 5.5 )].
Cardiac Rhythm and Conduction Abnormalities Inform patients that, due to its mechanism of action, LAMICTAL XR could lead to irregular or slowed heart rhythm. This risk is increased in patients with underlying cardiac disease or heart conduction problems or who are taking other medications that affect heart conduction. Patients should be made aware of and report cardiac signs or symptoms to their healthcare provider right away.
Patients who develop syncope should lie down with raised legs and contact their healthcare provider [see Warnings and Precautions ( 5.4 )] . Suicidal Thinking and Behavior Inform patients, their caregivers, and families that AEDs, including LAMICTAL XR, may increase the risk of suicidal thoughts and behavior. Instruct them to be alert for the emergence or worsening of symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior or thoughts about self-harm.
Instruct them to immediately report behaviors of concern to their healthcare providers. Worsening of Seizures Instruct patients to notify their healthcare providers if worsening of seizure control occurs. Central Nervous System Adverse Effects Inform patients that LAMICTAL XR may cause dizziness, somnolence, and other symptoms and signs of central nervous system depression.
Accordingly, instruct them neither to drive a car nor to operate other complex machinery until they have gained sufficient experience on LAMICTAL XR to gauge whether or not it adversely affects their mental and/or motor performance. Pregnancy and Nursing Instruct patients to notify their healthcare providers if they become pregnant or intend to become pregnant during therapy and if they intend to breastfeed or are breastfeeding an infant. Encourage patients to enroll in the NAAED Pregnancy Registry if they become pregnant.
This registry is collecting information about the safety of AEDs during pregnancy. To enroll, patients can call the toll-free number 1-888-233-2334 [see Use in Specific Populations ( 8.1 )] . Inform patients who intend to breastfeed that LAMICTAL XR is present in breast milk and advise them to monitor their child for potential adverse effects of this drug.
Discuss the benefits and risks of continuing breastfeeding. Use of Estrogen-Containing Products, Including Oral Contraceptives Instruct women to notify their healthcare providers if they plan to start or stop use of oral contraceptives or other female hormonal preparations (including HRT). Starting estrogen-containing products, including oral contraceptives, may significantly decrease lamotrigine plasma levels, and stopping estrogen-containing oral contraceptives (including the pill-free week) may significantly increase lamotrigine plasma levels [see Warnings and Precautions ( 5.9 ), Clinical Pharmacology ( 12.…
💬 Medication Guide ▾
MEDICATION GUIDE LAMICTAL (la-MIK-tal) XR (lamotrigine) extended-release tablets What is the most important information I should know about LAMICTAL XR? 1. LAMICTAL XR may cause a serious skin rash that may cause you to be hospitalized or even cause death.
There is no way to tell if a mild rash will become more serious. A serious skin rash can happen at any time during your treatment with LAMICTAL XR, but is more likely to happen within the first 2 to 8 weeks of treatment. Children aged between 2 and 16 years have a higher chance of getting this serious skin rash while taking LAMICTAL XR.
LAMICTAL XR is not approved for use in children younger than 13 years. The risk of getting a serious skin rash is higher if you: • take LAMICTAL XR while taking valproate [DEPAKENE (valproic acid) or DEPAKOTE (divalproex sodium)]. • take a higher starting dose of LAMICTAL XR than your healthcare provider prescribed. • increase your dose of LAMICTAL XR faster than prescribed. The risk of serious skin reactions may be associated with a variant in genes called HLA‑B*1502 in people from Asian origin (mainly of Han Chinese and Thai origin).
See “ Before taking LAMICTAL XR, tell your healthcare provider about all of your health conditions” . Call your healthcare provider right away if you have any of the following: LAMICTAL XR (lamotrigine) extended-release tablets 25 mg, yellow with white center Imprinted with LAMICTAL XR 25 50 mg, green with white center Imprinted with LAMICTAL XR 50 100 mg, orange with white center Imprinted with LAMICTAL XR 100 200 mg, blue with white center Imprinted with LAMICTAL XR 200 250 mg, purple with white center Imprinted with LAMICTAL XR 250 300 mg, gray with white center Imprinted with LAMICTAL XR 300 What is LAMICTAL XR? • LAMICTAL XR is a prescription medicine used: o together with other medicines to treat primary generalized tonic-clonic seizures and partial-onset seizures in people aged 13 years and older. o alone when changing from 1 other medicine used to treat partial-onset seizures in people aged 13 years and older. • It is not known if LAMICTAL XR is safe or effective in children younger than 13 years.
Other forms of LAMICTAL can be used in children aged 2 to 12 years. • It is not known if LAMICTAL XR is safe or effective when used alone as the first treatment of seizures. Do not take LAMICTAL XR: • if you have had an allergic reaction to lamotrigine or to any of the inactive ingredients in LAMICTAL XR. See the end of this leaflet for a complete list of ingredients in LAMICTAL XR.
Before taking LAMICTAL XR, tell your healthcare provider about all of your health conditions, including if you: • have had a rash or allergic reaction to another antiseizure medicine. • are of Asian origin. have had HLA testing before, and know you are carrying the genetic variant, HLA‑B*1502. • have or have had depression, mood problems, or suicidal thoughts or behavior. • have a history of heart problems or irregular heart beats or any of your family members have any heart problem, including genetic abnormalities. • have had aseptic meningitis after taking LAMICTAL (lamotrigine) or LAMICTAL XR. • are taking estrogen-containing products, including oral contraceptives (birth control pills) or other female hormonal medicines (such as hormone replacement therapy).
Do not start or stop taking birth control pills or other female hormonal medicine until you have talked with your healthcare provider. Tell your healthcare provider if you have any changes in your menstrual pattern such as breakthrough bleeding. Stopping these medicines while you are taking LAMICTAL XR may cause side effects (such as dizziness, lack of coordination, or double vision).
Starting these medicines may lessen how well LAMICTAL XR works. • are pregnant or plan to become pregnant. It is not known if LAMICTAL XR may harm your unborn baby. If you become pregnant while taking LAMICTAL XR, talk to your healthcare provider about registering with the North American Antie…