LAMICTAL

What it is

LAMICTAL contains lamotrigine. LAMICTAL is available as dispersible/chewable tablets and uncoated tablets. Strengths listed on the PBS include 5 mg, 25 mg, 50 mg, 100 mg, and 200 mg tablets.

Approved indications

— Treatment of partial and generalised seizures in adults and children — Prevention of depressive episodes in patients with bipolar disorder

Dosing overview

LAMICTAL is used as add-on therapy and has also been found effective as monotherapy following withdrawal of concomitant anti-epileptic drugs. Initial monotherapy treatment in newly diagnosed paediatric patients is not recommended. For adults and children over 12 years of age in monotherapy, the initial dose is 25 mg once daily for two weeks, followed by 50 mg once daily for two weeks, then increased by a maximum of 50 to 100 mg every one to two weeks until optimal response is achieved, with a usual maintenance dose of 100 to 200 mg daily given once daily or as two divided doses. For patients taking sodium valproate as add-on therapy, the initial dose is 25 mg every alternate day for two weeks, followed by 25 mg once daily for two weeks, then increased by a maximum of 25–50 mg every one to two weeks, with a usual maintenance dose of 100 to 200 mg daily. For patients not taking sodium valproate as add-on therapy, the initial dose is 50 mg once daily for two weeks, followed by 100 mg daily in two divided doses for two weeks, then increased by a maximum of 100 mg every one to two weeks, with a usual maintenance dose of 200 to 400 mg daily as a divided dose.

Key safety warnings

Severe, potentially life-threatening rashes have been reported in association with the use of lamotrigine, particularly in children, and LAMICTAL should be discontinued at the first sign of rash unless the rash is clearly not drug related. Careful incremental titration of the dose may decrease the severity of skin rashes. When restarting LAMICTAL after discontinuation, prescribers should assess the need for dose escalation, since the risk of serious rash is associated with high initial doses and exceeding recommended dose escalation; the greater the interval of time since the previous dose, the more consideration should be given to escalation to maintenance dose, and when the interval exceeds five half-lives, 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 unless the potential benefit clearly outweighs the risk.

PBS listing

LAMICTAL tablets are listed on the PBS in strengths of 5 mg, 25 mg, 50 mg, 100 mg, and 200 mg, with four PBS items per strength. All strengths are restricted. Ex-manufacturer prices are A$4.79 for 5 mg, A$7.98 for 25 mg, A$7.46 for 50 mg, A$10.60 for 100 mg, and A$15.94 for 200 mg.

Regulatory history

LAMICTAL lamotrigine tablets in 25 mg, 50 mg, 100 mg, and 200 mg strengths were first registered on the ARTG on 2 December 1993. Dispersible/chewable tablet formulations in 5 mg, 25 mg, and 100 mg strengths were registered on 26 April 1995. Additional dispersible/chewable strengths of 50 mg and 200 mg were registered on 27 May and 10 June 1997 respectively. The 2 mg dispersible/chewable tablet formulation was registered on 12 January 2001.