In order to improve patient compliance and decrease toxicity of antiepileptic drugs (AEDs), the recent strategy for epilepsy management has been to expand the use of extended-release (XR) formulations. Lamotrigine (LTG), an AED with broad efficacy, is available as a twice-daily immediate-release formulation. A once-daily XR formulation of LTG (LTG-XR) is currently being developed. LTG-XR tablets contain a modified-release eroding matrix formulation designed to control the dissolution rate of LTG. The bioavailability of LTG-XR is similar to that of LTG-IR, except in patients taking enzyme-inducing AEDs in whom the bioavailability of LTG-XR is 21% lower. In adult drug-resistant partial epilepsy, adjunctive LTG-XR effectively reduces the seizure frequency and is well tolerated. Trials in an elderly population with partial epilepsy as well as in adults with refractory primary tonic-clonic seizures are underway. Once-daily LTG-XR may represent a future option for patients with poor compliance to twice-daily immediate-release LTG.