Lamotrigine, like all antiepileptic drugs, can be effective when used as monotherapy or adjunctive therapy. In general, adverse effects are reduced when monotherapy is employed. The most frequent adverse effect prompting withdrawal of lamotrigine is rash. This potentially life-threatening adverse effect occurs more frequently in children, is increased when a rapid dose titration schedule is employed, and is greater when lamotrigine is prescribed in combination with valproate. The availability of lamotrigine and other antiepileptic drugs represents a major advance for the treatment of childhood epilepsy. The challenge in using all of the new antiepileptic drugs, including lamotrigine, is to balance the expected improved efficacy with the potentially serious adverse effects. (J Child Neurol 1997;12(Suppl 1):S48-S52).