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
A patient with recent onset primary generalized epilepsy, develops drug reaction and skin rash and neutropenia due to phenytoin sodium. The most appropriate course of action is: 
Select and explain. 
A. Shift to sodium valproate, B. Shift to clonazepam, C. Shift to ethosuximide, D. Restart phenytoin after 2 weeks
A: Shift to sodium valproate
Answer: A: Shift to sodium valproate 
Explanation: (Ref: Katzung, 14th ed. pg. 418-19; KDT 6th ed. pg. 405)Hypersensitivity reactions like rashes, DLE, lymphadenopathy and neutropenia require that phenytoin to be stopped.