Type-based Antiepileptic Drugs segmentation structures the market by pharmacological class, reflecting both prescriber familiarity and payer reimbursement tiers. First-generation agents (phenytoin, valproate, carbamazepine) still account for roughly 30% of global volume, driven by low cost and decades of real-world evidence, yet their share is eroding as guidelines emphasize tolerability. Second-generation molecules (lamotrigine, levetiracetam, topiramate) generate the largest revenue sliceโabout 45%โbecause of superior pharmacokinetics and broader label extensions into psychiatry. Third-generation offerings (lacosamide, perampanel, brivaracetam) are growing above market CAGR, propelled by hospital formularies seeking reduced drug-interaction burden, although unit pricing pressure tempers absolute value. Generics dominate first- and second-generation segments, while patent-protected third-generation brands command premium pricing, illustrating how market taxonomy shifts as exclusivity cliffs mature.