OBJECTIVES: Juvenile myoclonic epilepsy (JME) is one of the most common epilepsy syndromes accounting for approximately 7% of all cases of epilepsy. Choosing an appropriate antiepileptic drug (AED) is essential for the proper management of JME because of the possibility of exacerbation of seizures by some AEDs and the adverse effect profiles of effective drugs. This study aims to estimate the incremental budgetary impact of introducing levetiracetam adjunctive therapy for JME patients in Scotland. METHODS: A budget impact model was built to estimate the additional costs or savings generated by the introduction of levetiracetam adjunctive therapy for JME patients. The model was designed from the Scottish NHS perspective for a 3-year time horizon. Prevalence and incidence data of epilepsy were obtained from published literature. Scottish population estimates were based on mid-2005 estimates from the General Register Office of Scotland (2006). Levetiracetam adjunctive therapy was compared with topiramate adjunctive therapy. As resources used relating to general care, management of associated adverse events and of seizures were assumed to be the same for both adjunctive therapies, only drug acquisition costs were considered in this analysis. RESULTS: It is estimated that there are 2841 current cases and 142 new cases of JME each year. Based on levetiracetam market uptake, the number of patients with JME receiving levetiracetam is expected to be 28, 71, and 128 over the next 3 years. The incremental cost of using levetiracetam compared to topiramate adjunctive treatment is expected to be £5 per patient per year, resulting in an incremental budget impact of £156 to £698 over the next three years. This increase is mainly due to the increased market uptake of levetiracetam. CONCLUSION: Introducing levetiracetam adjunctive therapy for JME patients is predicted to have a limited impact on the Scottish NHS budget over a 3-year time period.