Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined by generalized multiple type seizures, slowness of intellectual growth, and a specific EEG disturbance. Children affected might previously have infantile spasms or underlying brain disorder but etiology can be idiopathic. LGS seizures are often treatment resistant and the long term prognosis is poor. Key words: epilepsy, intellectual growth DOI: 10.3126/jnps.v30i1.2461Journal of Nepal Paediatric Society Vol.30(1) 2010 50-52