Lamictal

Lamictal Dosage/Direction for Use

lamotrigine

Manufacturer:

GlaxoSmithKline Indonesia
Full Prescribing Info
Dosage/Direction for Use
Lamictal tablets should be swallowed whole, and should not be chewed or crushed.
If a calculated dose of Lamictal eg, for use in children (epilepsy only) or patients with hepatic impairment, cannot be divided into multiple lower strength tablets, the dose to be administered is that equal to the nearest lower strength of whole tablets.
Restarting Therapy: Prescribers should assess the need for escalation to maintenance dose when restarting Lamictal in patients who have discontinued Lamictal for any reason, since the risk of serious rash is associated with high initial doses and exceeding the recommended dose escalation for Lamictal (see Precautions). The greater the interval of time since the previous dose, the more consideration should be given to escalation to the maintenance dose. When the interval since discontinuing Lamictal exceeds 5 half-lives (see Pharmacokinetics under Actions), Lamictal should generally be escalated to the maintenance dose according to the appropriate schedule.
It is recommended that Lamictal not be restarted in patients who have discontinued due to rash associated with prior treatment with Lamictal unless the potential benefit clearly outweighs the risk.
Epilepsy: When concomitant antiepileptic drugs are withdrawn to achieve Lamictal monotherapy or other AEDs are added-on to treatment regimens containing lamotrigine, consideration should be given to the effect this may have on lamotrigine pharmacokinetics (see Interactions).
Adults >12 years: See Table 1.
Dosage in Epilepsy Monotherapy: The initial Lamictal dose in monotherapy is 25 mg once daily for 2 weeks, followed by 50 mg once daily for 2 weeks. Thereafter, the dose should be increased by a maximum of 50-100 mg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 100-200 mg daily given once daily or as 2 divided doses. Some patients have required Lamictal 500 mg daily to achieve the desired response.
Because of a risk of rash, the initial dose and subsequent dose escalation should not be exceeded (see Precautions).
Dosage in Epilepsy Add-On Therapy: In patients taking valproate with/without any other AED, the initial Lamictal dose is 25-mg every alternate day for 2 weeks, followed by 25 mg once daily for 2 weeks. Thereafter, the dose should be increased by a maximum of 25-50 mg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 100-200 mg daily given once a day or in 2 divided doses.
In those patients taking concomitant AEDs or other medications (see Interactions) that induce lamotrigine glucuronidation with/without other AEDs (except valproate), the initial Lamictal dose is 50 mg once daily for 2 weeks, followed by 100 mg daily given in 2 divided doses for 2 weeks.
Thereafter, the dose should be increased by a maximum of 100 mg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 200-400 mg daily given in 2 divided doses.
Some patients have required Lamictal 700 mg daily to achieve the desired response.
In those patients taking other medications that do not significantly inhibit or induce lamotrigine glucuronidation (see Interactions), the initial Lamictal dose is 25 mg once daily for 2 weeks, followed by 50 mg once daily for 2 weeks. Thereafter, the dose should be increased by a maximum of 50-100 mg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve an optimal response is 100-200 mg daily given once daily or as 2 divided doses. (See Table 1.)


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Because of a risk of rash the initial dose and subsequent dose escalation should not be exceeded (see Precautions).
Children 2-12 years: See Table 2.
In patients taking valproate with/without any other AED, the initial Lamictal dose is 0.15 mg/kg bodyweight given once daily for 2 weeks, followed by 0.3 mg/kg once daily for 2 weeks. Thereafter, the dose should be increased by a maximum of 0.3 mg/kg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 1-5 mg/kg given once daily or in 2 divided doses, with a maximum of 200 mg daily.
In those patients taking concomitant AEDs or other medications (see Interactions) that induce lamotrigine glucuronidation with/without other AEDs (except valproate), the initial Lamictal dose is 0.6 mg/kg bodyweight daily given in 2 divided doses for 2 weeks, followed by 1.2 mg/kg daily given in 2 divided doses for 2 weeks. Thereafter, the dose should be increased by a maximum of 1.2 mg/kg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 5-15 mg/kg daily given in 2 divided doses, with a maximum of 400 mg daily.
In patients taking other medications that do not significantly inhibit or induce lamotrigine glucuronidation (see Interactions), the initial Lamictal dose is 0.3 mg/kg bodyweight given once daily or in 2 divided doses for 2 weeks, followed by 0.6 mg/kg given once daily or in 2 divided doses for 2 weeks. Thereafter, the dose should be increased by a maximum of 0.6 mg/kg every 1-2 weeks until the optimal response is achieved. The usual maintenance dose to achieve optimal response is 1-10 mg/kg given once daily or in 2 divided doses, with a maximum of 200 mg daily. To ensure a therapeutic dose is maintained the weight of a child must be monitored and the dose reviewed as weight changes occur. (See Table 2.)


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Because of a risk of rash the initial dose and subsequent dose escalation should not be exceeded (see Precautions). It is likely that patients 2-6 years will require a maintenance dose at the higher end of the recommended range.
Children <2 years: There is insufficient information on the use of Lamictal in children aged <2 years.
Bipolar Disorder: Adults ≥18 years: Because of the risk of rash, the initial dose and subsequent dose escalation should not be exceeded (see Precautions).
Lamictal is recommended for use in bipolar patients at risk for a future depressive episode.
The following transition regimen should be followed to prevent recurrence of depressive episodes. The transition regimen involves escalating the dose of Lamictal to a maintenance stabilisation dose >6 weeks (see Table 3) after which other psychotropic and/or antiepileptic drugs can be withdrawn, if clinically indicated (see Table 4).
Adjunctive therapy should be considered for the prevention of manic episodes, as efficacy with Lamictal in mania has not been conclusively established. (See Table 3.)


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Adjunct Therapy with Inhibitors of Lamotrigine Glucuronidation eg, Valproate: In patients taking glucuronidation inhibiting concomitant drugs eg, valproate the initial Lamictal dose is 25 mg every alternate day for 2 weeks, followed by 25 mg once a day for 2 weeks. The dose should be increased to 50 mg once a day (or in 2 divided doses) in week 5. The usual target dose to achieve optimal response is 100 mg daily given once a day or in 2 divided doses. However, the dose can be increased to a maximum daily dose of 200 mg, depending on clinical response.
Adjunct Therapy with Inducers of Lamotrigine Glucuronidation in Patients not Taking Inhibitors eg, Valproate: This dosage regimen should be used with phenytoin, carbamazepine, phenobarbitone, primidone and other drugs known to induce lamotrigine glucuronidation (see Interactions). In those patients currently taking drugs that induce lamotrigine glucuronidation and not taking valproate, the initial Lamictal dose is 50 mg once a day for 2 weeks, followed by 100 mg daily given in 2 divided doses for 2 weeks. The dose should be increased to 200 mg daily given as 2 divided doses in week 5. The dose may be increased in week 6 to 300 mg daily however, the usual target dose to achieve optimal response is 400 mg daily given in 2 divided doses which may be given from week 7.
Monotherapy with Lamictal or Adjunctive Therapy in Patients Taking Other Medications that do not Significantly Induce or Inhibit Lamotrigine Glucuronidation (see Interactions): The initial Lamictal dose is 25 mg once a day for 2 weeks, followed by 50 mg once a day (or in 2 divided doses) for 2 weeks. The dose should be increased to 100 mg daily in week 5. The usual target dose to achieve optimal response is 200 mg daily given once a day or as 2 divided doses. However, a range of 100-400 mg was used in clinical trials.
Once the target daily maintenance stabilisation dose has been achieved, other psychotropic medications may be withdrawn as laid out in the dosage schedule below (see Table 4).


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Following Withdrawal of Adjunct Therapy with Inhibitors of Lamotrigine Glucuronidation eg, Valproate: The dose of Lamictal should be increased to double the original target stabilisation dose and maintained at this, once valproate has been terminated.
Following Withdrawal of Adjunct Therapy with Inducers of Lamotrigine Glucuronidation Depending on Original Maintenance Dose: This regimen should be used with phenytoin, carbamazepine, phenobarbitone, primidone or other drugs known to induce Lamictal glucuronidation (see Interactions). The dose of Lamictal should be gradually reduced over 3 weeks as the glucuronidation inducer is withdrawn.
Following Withdrawal of Adjunct Therapy with Other Medications that do not Significantly Inhibit or Induce Lamotrigine Glucuronidation (see Interactions): The target dose achieved in the dose escalation programme should be maintained throughout withdrawal of the other medication.
Adjustment of Lamictal Daily Dosing in Patients with Bipolar Disorders Following Addition of Other Medications: There is no clinical experience in adjusting the Lamictal daily dose following the addition of other medications. However, based on drug interaction studies, the following recommendations can be made (see Table 5).


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Discontinuation of Lamictal in Patients with Bipolar Disorder: In clinical trials, there was no increase in the incidence, severity or type of adverse experiences following abrupt termination of Lamictal versus placebo. Therefore, patients may terminate Lamictal without a step-wise reduction of dose.
Children and Adolescents (<18 years): Lamictal is not indicated for use in bipolar disorder in children and adolescents aged <18 years (see Precautions). Safety and efficacy of Lamictal in bipolar disorder has not been evaluated in this age group. Therefore, a dosage recommendation cannot be made.
General Dosing Recommendations for Lamictal in Special Patient Populations: Women Taking Hormonal Contraceptives: Starting Lamictal in Patients Already Taking Hormonal Contraceptives: Although an oral contraceptive has been shown to increase the clearance of lamotrigine (see Precautions and Interactions), no adjustments to the recommended dose escalation guidelines for Lamictal should be necessary solely based on the use of hormonal contraceptives. Dose escalation should follow the recommended guidelines based on whether lamotrigine is added to valproate (an inhibitor of lamotrigine glucuronidation), or to an inducer of lamotrigine glucuronidation, or whether Lamictal is added in the absence of valproate, or an inducer of lamotrigine glucuronidation (see Table 1 for epilepsy and Table 3 for bipolar patients).
Starting Hormonal Contraceptives in Patients Already Taking Maintenance Doses of Lamictal and not Taking Inducers of Lamotrigine Glucuronidation: The maintenance dose of Lamictal may need to be increased by as much as 2-fold according to the individual clinical response (see Precautions and Interactions).
Stopping Hormonal Contraceptives in Patients Already Taking Maintenance Doses of Lamictal and Not Taking Inducers of Lamotrigine Glucuronidation: The maintenance dose of Lamictal may need to be decreased by as much as 50% according to the individual clinical response (see Precautions and Interactions).
Use with Atazanavir/Ritonavir: Although atazanavir/ritonavir has been shown to reduce lamotrigine plasma concentrations (see Interactions), no adjustments to the recommended dose escalation guidelines for Lamictal should be necessary solely based on the use of atazanavir/ritonavir. Dose escalation should follow the recommended guidelines based on whether Lamictal is added to valproate (an inhibitor of lamotrigine glucuronidation), or to an inducer of lamotrigine glucuronidation, or whether Lamictal is added in the absence of valproate or an inducer of lamotrigine glucuronidation.
In patients already taking maintenance doses of Lamictal and not taking glucuronidation inducers, the Lamictal dose may need to be increased if atazanavir/ritonavir is added, or decreased if atazanavir/ritonavir is discontinued.
Hepatic Impairment: Initial, escalation and maintenance doses should generally be reduced by approximately 50% in patients with moderate (Child-Pugh grade B) and 75% in severe (Child-Pugh grade C) hepatic impairment. Escalation and maintenance doses should be adjusted according to clinical response (see Pharmacokinetics under Actions).
Renal Impairment: Caution should be exercised when administering Lamictal to patients' with renal failure. For patients with end-stage renal failure, initial doses of Lamictal should be based on patients AED regimen; reduced maintenance doses may be effective for patients with significant renal functional impairment (see Pharmacokinetics under Actions and Precautions).
Elderly (>65 years): No dosage adjustment from recommended schedule is required. The pharmacokinetics of Lamictal in this age group do not differ significantly from a non-elderly adult population.
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