Brief Overview:

Lamotrigine (Lamictal®) is a very popular anti-seizure medication which is generally very well tolerated and is effective in the treatment of many types of seizures. Lamotrigine exhibits one of the best safety profiles during pregnancy in comparison to other anti-seizure drugs. It is frequently used first-line for generalized-onset seizures and focal-onset seizures (e.g. complex partial seizures). However, with regard to infantile spasms, there is no compelling evidence that it is effective, and there have been several reports that it may worsen infantile spasms. Also of note, lamotrigine can frequently worsen myoclonic seizures, though paradoxically it appears to provide benefit in a substantial minority of patients with myoclonic seizures.

The main hindrance for the use of lamotrigine is its association with a very serious rash known as Stevens-Johnson Syndrome (SJS) and related disorders known as erythema multiforme and toxic epidermal necrolysis. This rash can affect the entire body, including the mucus membranes (e.g. eyes, mouth, nostrils), and is often extremely severe and painful. Patients with SJS often require intensive treatment in burn units, and there are substantial risks of infection and other complications including death. In the general population, the annual risk of SJS is approximately 1 in 200,000. In the initial clinical trials of lamotrigine, the risk was approximately 1 in 300. Since the widespread adoption of protocols in which lamotrigine is started at a very low dose and slowly increased over several months, the risk of SJS has been substantially reduced, though the exact risk is difficult to quantify. It appears that with a slow dose escalation, patients either have an opportunity to develop tolerance to the drug, or discontinue the drug in the event of a miild rash, before symptoms become dangerous. As above, in spite of this rather alarming potential side effect, lamotrigine is a popular anti-seizure drug and often used first-line. 


The goal dose of lamotrigine ranges from approximately 3 to 10 mg/kg/day, divided in 2 doses. There is also an extended-release preparation which can be administered once daily. Depending on other drugs taken at the same time, especially valproic acid (Depakote®), the starting dose is usually very small, and increased to goal dose over a few months.

Side Effects:

In addition to SJS (described above), lamotrigine is associated with many relatively mild side effects typical of other drugs (e.g. nausea, vomiting, rash, headache, fatigue, etc). In rare cases, lamotrigine has been associated with organ toxicity (e.g. liver failure, pancreatitis, bone marrow toxicity). Nevertheless, most patients who take lamotrigine do not suffer any side effects, and periodic blood tests to monitor organ function are typically unnecessary.


This medication should be administered only under the direct supervision of a physician.

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