The current status of taurine in epilepsy.

The part played by taurine in epileptogenesis is still controversial. A cortical deficit of the amino acid has been confirmed only in certain types of human and animal epilepsy, and the effects of an artificial change of taurine cortical concentration are inconclusive. An increase is associated with a reduced susceptibility to epileptogenic agents but not with the prevention of epilepsy, while a decrease may precipitate seizure activity in genetically susceptible rats but does not bring about spontaneous epileptic activity in normal animals. The role of taurine in synaptic transmission is uncertain (specific inhibitory neurotransmitter, indirect modulator of membrane excitability), and its antiepileptic action, confirmed in several models of experimental epilepsy and in short-term clinical studies, does not seem to possess major clinical relevance since trials with a longer follow-up gave unsatisfactory results. Taurine's limited diffusibility across the blood-brain barrier may be the main factor restricting the antiepileptic effect of this compound.