The aim of this study was to assess the possible antinociceptive affects of the novel antiepileptic agent levetiracetam (LEV, ucb L059) using both in vivo behavioural and cellular electrophysiological testings. Antinociceptive efficacy of levetiracetam was assessed in a mice model for painful diabetic neuropathy using the in vivo nociceptive behavioural “hot-plate test”. Subsequent to behavioural testing, electrophysiological measurements were performed on cultured neurones of the rat dorsal root ganglia (DRG) using the whole cell patch-clamp technique. The hot plate test consisted of placing individual mice (adult male Balb/C) on the hot-plate at 50±0.1 degrees and timing the delay for the first hind paw lift (nociceptive threshold). After obtaining control values, diabetes was induced by injection of streptozocin (200 mg/kg i.p.) and 2 weeks after induction of diabetes (serum glucose ≥ 400 mg/dL) levetiracetam was administered intraperitoneally and hot-plate tests were repeated. Pain threshold values were determined and analyzed by Kruskal-Wallis One-way Analysis of Variance (ANOVA) followed by a pairwise comparison between vehicle and each LEV treated group using a Dunnett’s t-test on the ranked data. LEV (60, 300 and 900 mg/kg) had no significant effect on the nociceptive threshold in normal mouse (n=8 for each dose, P>0.05). There were significant decreases in pain threshold latency in diabetic mice compared to normal healthy group and these were significantly and dose-dependently restored by much lower doses of LEV (20, 100 and 200 mg/kg) in a reversible manner. We next evaluated the effects of levetiracetam on isolated neonatal rat DRG neurones with the aim of assessing cellular mechanism of its antinociceptive action. Effects of LEV (30, 100 and 300 uM) on membrane potential and action potential (AP) parameters (thresholds, peak amplitude, duration, after potentials, decay time) and input resistance were investigated. The effects of LEV on these parameters was dose dependent; 100 and 300 uM LEV caused hyperpolarization of the resting membrane potential, and increased the mean amplitude of after hyperpolarisations and input resistance (n=7, P<0.05) without significantly effecting other parameters of action potentials. Estimated reversal potentials of LEV-induced hyperpolarizing currents were close to the E(K). In conclusion; results obtained by cellular biophysical procedures in in vitro experiments and in vivo behavioural tests with agreement lend support to the validation of the promising therapeutic potential of the novel antiepileptic agent LEV in treatment of neuropathic pain.