Anticonvulsant. Antagonizes GluR5 kainate receptors (IC50 = 0.46 μM), acts as a positive allosteric modulator of GABAA receptor-mediated currents, inhibits Nav channels (IC50 = 48.9 μM) and inhibits L-type Ca2+ channels. Also inhibits carbonic anhydrase (CA) (Ki values are 0.1 and 0.2 μM at rat CA II and CA IV respectively), which lowers intracellular neuronal pH.