The invention relates to the use of cannabidiol (CBD) at a dose of greater than 300mg/day in combination with a standard anti epileptic drug (SAED) which acts via sodium or calcium channels for use in the treatment of epilepsy.The SAED is preferably one which • modifies low threshold or transient neuronal calcium currents or • reduces high frequency neuronal firing and sodium dependent action potentials and enhances GABA effects. Preferred SAEDs are ethosuximide and valproate.
