Fig. (1).

Suggested Algorithmic Approach for Initiating and Carrying Out Transitional Polytherapy. There are two potential pathways for using the algorithm which consider the alternative common clinical scenarios of either breakthrough seizures (beginning in upper left corner) or adverse effects (lower right corner) during initial monotherapy. If a patient experiences breakthrough seizures without adverse effects on monotherapy, the algorithm suggests further titration of high dose monotherapy until a “therapeutic plateau” (i.e., a maximal level of seizure reduction response) is reached, then progressing to a “Fixed-dose” transitional polytherapy strategy. Alternatively, if the patient experiences adverse effects, a “Flex-dose” strategy is most appropriate, which involves simultaneous reduction and tapering of the primary baseline antiepileptic drug (AED) while titrating the new adjunctive AED. The anticipated successful outcomes of these strategies would be seizure freedom on high dose monotherapy, seizure freedom following conversion to a new monotherapy, or a trial of chronic maintenance polytherapy with both the baseline and adjunctive AED.