This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pediatrics
[{'content': 'Drug of choice in Absence Seizure \nSelect and explain. \nA. Carbamazepine, B. Phenytoin, C. ACTH, D. Ethosuximide', 'role': 'user'}, {'content': "Answer: D \nExplanation: 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 ethosuximide's 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", 'role': 'assistant'}]