FDA要求generic和名牌药接近，没要求一样。大家一定要读上面文章!!!

http://fortune.com/2013/01/10/are-generics-really-the-same-as-branded-drugs/

In the case of some medications, small differences can have large effects. Doctors are most concerned about so-called narrow therapeutic index drugs. These treat conditions like epilepsy, hypertension, and endocrine disorders that require precise dosing, where minor variations can lead to life-threatening complications. Medical societies such as the American Academy of Neurology, the Endocrine Society, and the American Heart Association contend that a switch to generics can cause adverse events, and they oppose doing so without a doctor’s approval.