The invention relates to the use of cannabidiol (CBD), at a dose of greater than 300 mg/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.
