This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Pharmacology
[{'content': 'Which antiepileptic drug can lead to this adverse effect: \nSelect and explain. \nA. Phenytoin, B. Carbamazepine, C. Valproate, D. Lamotrigine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (A) PhenytoinThe figure shows the gum hypertrophy which is caused by phenytoinThe mechanism of action of antiepileptic drugsMain mechanismDrugNa Channel blockersPhenytoinCarbamazepineLamotrigineValproateStimulate GABA-BZD Cl channel complesBarbituratesBenzodiazepinesInhibit GABA transaminaseVigabatrinInhibit GAT-1TiagabineAct on SV2ALevetiracetamOpen K+ ChannelsRetigabineBlock NMDA receptorsFelbamateBlock AMPA receptorsPerampanelBlock L type Ca ChannelsEthosuximide', 'role': 'assistant'}]