Names and pronunciation
(la-moe′tri-geen) LaMICtal, Lamictal CD, LaMICtal ODT, LaMICtal, Starter, LaMICtal XR, Subvenite, Subvenite Starter Kit-Blue, Subvenite Starter Kit- Green, Subvenite Starter Kit- Orange
Source page 753
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Individual generic drug information
Extracted information for lamoTRIgine only.
(la-moe′tri-geen) LaMICtal, Lamictal CD, LaMICtal ODT, LaMICtal, Starter, LaMICtal XR, Subvenite, Subvenite Starter Kit-Blue, Subvenite Starter Kit- Green, Subvenite Starter Kit- Orange
Source page 753
Func. class.: Anticonvulsant— miscellaneous
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Chem. class.: Phenyltriazine
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Do not confuse: lamoTRIgine/lamiVUDine/levothyroxine LaMICtal/LamISIL
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ACTION: Inhibits voltage-sensitive sodium channels, thus decreasing seizures
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USES: Adjunct for the treatment of par- tial, tonic-clonic seizures; children with Lennox-Gastaut syndrome, bipolar disorder
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Unlabeled uses: Absence seizures
Source page 753
Extracted information for lamoTRIgine only.
CONTRAINDICATIONS: Hyper- sensitivity, mania Precautions: Pregnancy (cleft lip/palate during 1st trimester), breastfeeding, geriat- ric patients, cardiac/renal/hepatic disease, severe depression, suicidal thoughts, blood dyscrasias, children <16 yr, risk of hemo- phagocytic lymphohistiocytosis (HLH), abrupt discontinuation, autoimmune dis- ease, SLE
Source page 753
Black Box Warning: Serious rash Black Box Warning: Rash (Stevens- Johnson syndrome, toxic epidermal necrolysis) in pediatric patients: prod- uct should be discontinued at first sign of rash; more common in those taking mul- tiple products for seizures; rash usually occurs during 2-8 wk of therapy • Bipolar disorder: suicidal thoughts/ behaviors • DRESS: monitor for fever, rash, lymphade nopathy; may occur with hepatitis, nephritis, myocarditis; discontinue immediately, may involve multiple organ systems • Risk of hemophagocytic lymphohis- tiocytosis (HLH): monitor for persistent fevers, rash, enlarged liver/spleen/lymph nodes, anemia, low platelets Black Box Warning: Rash: to notify prescriber immediately if rash, fever, or swollen lymph nodes occur • To notify prescriber immediately of sui cidal thoughts/behaviors, new or worsen ing depression, anxiety, aggression • Pregnancy/breastfeeding: to notify prescriber if pregnancy is planned or sus pected; to use a nonhormonal contracep tive; to enroll with the North American Antiepileptic Drug Pregnancy Registry at 888-233-2334 (www.aedpregnancyregis try.org); that product decreases folate; to avoid breastfeeding
Source pages 753, 755
SIDE EFFECTS CNS: Dizziness, ataxia, headache, fever, insomnia, tremor, depression, anxiety, suicidal ideation, seizures, poor concentration EENT: Nystagmus, diplopia, blurred vision GI: Nausea, vomiting, anorexia, abdomi nal pain, hepatotoxicity GU: Dysmenorrhea HEMA: Anemia, DIC, leukopenia, thrombocytopenia INTEG: Rash (potentially life-threatening), alopecia, photosensitivity CV: Chest pain, palpitations MS: Neck pain, myalgias SYST: Stevens-Johnson syndrome, angio edema, toxic epidermal necrolysis, DRESS
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INTERACTIONS Decrease: metabolic clearance of lamoTRIgine—valproic acid, CYP3A4 inhibitors Decrease: lamoTRIgine concentration— carBAMazepine, acetaminophen, phenytoin, primidone, PHENobarbital, OXcarbazepine Drug/Herb Increase: anticonvulsant effect—ginkgo Decrease: anticonvulsant effect—ginseng Drug/Lab False positive: PCP (rapid drug screen)
Source page 754
Extracted information for lamoTRIgine only.
DOSAGE AND ROUTES Seizures: monotherapy • Adult/adolescent ≥16 yr: PO 50 mg/ day while receiving 1 enzyme-inducing AED (carBAMazepine, PHENobarbital, phenytoin, primidone but not valproic acid) week 1-2, then increase to 100 mg divided bid week 3-4; maintenance 300- 500 mg/day; EXT REL 50 mg/day × 1-2 wk, then 100 mg/day week 3-4, then 200 mg/day week 5, then 300 mg/day week 6, then 400 mg/day week 7; after week 7, range is 400-600 mg/day • Adolescent <16 yr/child: PO 0.3 mg/ kg/day week 1-2, then 0.6 mg/kg/day week 3-4; depends on use of AED; usual L dose 4.5-7.5 mg/kg/day, max 300 mg/day Monotherapy for patients taking valproate • Adult/adolescent ≥16 yr receiving lamoTRIgine and valproate without enzyme-inducing drug: PO (immediate release) stabilize on valproate, target dose is 200 mg/day lamoTRIgine; if pa- tient is not taking lamoTRIgine 200 mg/ day, increase dose by 25-50 mg/day q1- 2wk to reach 200 mg/day; while main- taining lamoTRIgine 200 mg/day, de- crease valproate to 500 mg/day by ≤500 mg/day/wk, maintain valproate at 500 mg/day × 1 wk, then increase la- moTRIgine to 300 mg/day while de- creasing valproate 250 mg/day × 1 wk, then discontinue valproate and increase lamoTRIgine by 100 mg/day/wk to main- tenance of 500 mg/day Seizures: multiple therapy with valproate • Adult/adolescent ≥16 yr: PO 25 mg every other day, then 25 mg/day week 3-4, increase by 25-50 mg q1-2wk, maintenance 100-500 mg/day • Adolescent <16 yr/child: PO 0.1-0.2 mg/kg/day initially, then increase q2wk as needed to 1-5 mg/kg/day or 200 mg/day Hepatic dose • Adult: PO moderate hepatic impair ment or severe without ascites: reduce by 25%; severe hepatic impairment with as cites: reduce by 50% Absence seizures (unlabeled) • Adolescent/child 3-13 yr: PO 0.5 mg/ kg/day in 2 divided doses × 2 wk, then 1 mg/kg/day in 2 divided doses × 2 wk, adjusted q5days
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Available forms: Tabs 25, 100, 150, 200 mg; PO ext rel 25-50-100, 50-100- 200 mg titration kit; PO 25-100 mg starter kit; ext rel 25, 50, 100, 250, 300 mg; chew dispersible tabs 5, 25 mg; oral disintegrating tab 25, 50, 100, 200 mg; oral disintegrating tab 25-50, 50-100 mg, 25-50-100 mg titra- tion kit
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Administer: • Correct starter kit; severe side effects have occurred from incorrect starter kit • Discontinue all products gradually over ≥2 wk; abrupt discontinuation can in- crease seizures • All forms may be given without regard to meals • Extended-release product is not to be used for conversion to monotherapy for ≥2 antiepileptic products • Orange starter kit: for those NOT tak- ing carBAMazepine, phenytoin, PHENo- barbital, primidone, rifAMPin, valproate • Green starter kit: for those taking car- BAMazepine, phenytoin, PHENobarbital, primidone, rifAMPin but NOT valproate • Blue starter kit: for those taking valproate • If a dose is missed, take as soon as remembered unless next dose is in <4 hr, then skip and take next regularly scheduled dose • Chewable dispersible tab: may be swallowed whole, chewed, mixed in water or fruit juice; to mix, add to small amount of liquid in glass or spoon; tabs will dis- solve in 1 min, then mix in more liquid and swirl and swallow immediately; do not cut tabs in half • Orally disintegrating tabs: place on tongue, move around in mouth; when disin- tegrated, swallow; examine blister pack be- fore use, do not use if blisters are torn or missing • Extended-release tabs: swallow whole; do not cut, break, chew; without regard to food
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Extracted information for lamoTRIgine only.
Assess: • Seizure: duration, type, intensity, halo before seizure baseline and peri- odically
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Evaluate: • Therapeutic response: decrease in severity of seizures or of bipolar symp- toms
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CLINICAL CONSIDERATIONS
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Patient and caregiver information: • To take PO doses divided, with or after meals to decrease adverse effects; not to discontinue product abruptly because seizures may occur • To avoid hazardous activities until sta- bilized on product • To carry emergency ID; to notify prescriber of skin rash, increased sei- zure activity; to use sunscreen, pro- tective clothing if photosensitivity oc- curs
Source page 755
Extracted information for lamoTRIgine only.
PHARMACOKINETICS Half-life varies depending on dose; half- life 24 hr, 15 hr with enzyme inducers; rapidly, completely absorbed; metabo- lized by glucuronic acid conjunction; protein binding 55%; peak 1.4-2.3 hr, XR 4-10 hr; crosses placenta; excreted in breast milk
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Filter the extracted dose blocks for this individual drug.
Seizures: monotherapy
• Adolescent <16 yr/child: PO 0.3 mg/ kg/day week 1-2, then 0.6 mg/kg/day week 3-4; depends on use of AED; usual L dose 4.5-7.5 mg/kg/day, max 300 mg/day Monotherapy for patients taking valproate
Candidate age grouping · source pages 753, 754
Seizures: monotherapy
• Adolescent <16 yr/child: PO 0.1-0.2 mg/kg/day initially, then increase q2wk as needed to 1-5 mg/kg/day or 200 mg/day Hepatic dose
Candidate age grouping · source pages 753, 754
Seizures: monotherapy
• Adolescent/child 3-13 yr: PO 0.5 mg/ kg/day in 2 divided doses × 2 wk, then 1 mg/kg/day in 2 divided doses × 2 wk, adjusted q5days
Candidate age grouping · source pages 753, 754