Abstract: This paper explores the relevance between data protection system and drug availability through the American lamotrigine(lamictal^® )case. Results indicated that drug data protection system delays the marketing of genetics, hinders the pricing regulation of innovative drugs timely and effectively, and affects drug availability severely. With reference to America, it is urgent to design the scope of data protection system reasonably, and set the first generic drug regime and other supporting measures so as to reduce the negative effects of drug data protection system and improve the health benefits of the public.