This quote comes from this site, which discusses the "bioequavilence" of generic drugs:Do all generic drugs work the same way?
No, there are some differences. The Food and Drug Administration grades generic drugs for bioequivalence, and publishes that information in a compendium commonly referred to as the Orange Book. A small proportion of generic drugs (4 percent) are rated as "non-therapeutically equivalent," and a handful of those are considered "non-equivalent." If you're interested in looking up the generics you use and discussing that information with your doctor, the Orange Book is available online on the FDA's Web site.
http://healthresources.caremark.com/topic/genericsafety
Here is the online FDA Orange Book that is mentioned in the article:
http://www.fda.gov/cder/ob/
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