<prompt> Drug of choice in Absence SeizureCarbamazepinePhenytoinACTHEthosuximide  <response>: Ethosuximide is the drug of choice in Absence seizures. Ethosuximide: Ethosuximide Zarontin, a succinimide, has been considered an effective agent for the treatment of absence seizures since the mid-20th century.Although ethosuximides mechanism of action is not fully understood, the blockade of a specific voltage-gated calcium channel the T channel in thalamic neurons appears integral to its antiepileptic activity. This blockade suppresses thalamic excitability, which is thought to be necessary for sustaining the characteristic spike-wave discharge of absence seizures. Serious adverse events linked to ethosuximide include agranulocytosis, aplastic anemia, pancytopenia, Stevens-Johnson syndrome SJS, and systemic lupus erythematosus; however, these occur rarely and the medication is generally well tolerated. Reference: GHAI Essential pediatrics, 8th edition 