多数国家已经建立或正在建立药物立法体制,藉以保证为国民提供安全及有效的药物.然而在药物批准以及上市后,即使是最完善和最严密的药物管理制度,也不能保证获批上市后的药物不出现新的作用或不良反应.实际上,药物上市后不出现此类新的情况才是怪事.药物的不受欢迎的发展,可能同其效果有关,同样也可能与其不良反应或相互作用有关.最初一种药物经临床试验所显现的效果,在较大的人群中应用该药物时并不能总是再获得验证. Most countries have established or are in the process of establishing a drug legislation system to ensure the provision of safe and effective medicines to their citizens. However, even after drug approval and listing, even the most complete and stringent drug administration system can not guarantee the successful listing of Drugs do not appear new or adverse reactions.In fact, the drug does not appear after the listing of such a new situation is a strange thing.The unwelcome development of drugs, may be related to its effectiveness, but also may be adverse reactions or interactions The effect of the first drug, which has been shown in clinical trials, can not always be validated in larger populations.