Zonisamide – a new generation antiepileptic drug – features a multidirectional mechanism of action. The antiepileptic effect of zonisamide involves blockade of voltage-dependent Na+ and Ca2+ T-type channels, which have a most important role in membrane excitability, suggesting that zonisamide disrupts neuronal synchronized firings and epileptic activity resulting in a limitation of initiation or propagation of seizure. As an anticonvulsant it is used in the treatment of partial and generalized seizures mixed with adults and children, both in combination and in monotherapy. Zonisamide has also been approved for the treatment of Parkinson’s disease. In several double-blind, randomized, multicentre trials, carried out on Parkinson’s disease patients, who showed insufficient response to L-dopa treatment, zonisamide significantly improved motor functions determined by beneficial changes in the total score of the Unified Parkinson’s Disease Rating Scale (UPDRS). It is known that the drug increases dopaminergic transmission. New research shows that both, dopaminergic and non-dopaminergic mechanisms could equally be involved. Many authors emphasizes the importance neuroprotective activity of zonisamide. However, there are still some aspects that need to be explained in further studies. Clinical trials are conducted to evaluate its efficacy in bipolar disorder, neuropathic pain and migraine, anxiety disorders, eating disorders and in patients with alcohol dependence. Results of the studies are promising and provide a new possibilities of zonisamide application. However, there is a strong need to expand research in this area.

zonisamide, mechanism of action, drug safety, indications, new directions for zonisamide use