Counterexamples to your expression of personal belief are the drugs and medical devices that have already been withdrawn from the market for all indications or for some previous indications by the FDA. The list below is far from exhaustive.
http://en.wikipedia.org/wiki/Temafloxacin
http://en.wikipedia.org/wiki/Fen-phen
http://en.wikipedia.org/wiki/Terfenadine
http://en.wikipedia.org/wiki/Troglitazone
http://en.wikipedia.org/wiki/Tegaserod
(See also page 45 of an FDA report.)
http://www.fda.gov/downloads/AboutFDA/CentersOffices/CDER/Wh...
Other drugs have been withdrawn voluntarily from the market by the companies that make them when problems have appeared in their use.
http://en.wikipedia.org/wiki/Cerivastatin
http://en.wikipedia.org/wiki/Rofecoxib
Other drugs approved in other countries never received FDA approval in the first place.
http://en.wikipedia.org/wiki/Tolrestat
http://en.wikipedia.org/wiki/Ximelagatran
http://en.wikipedia.org/wiki/Rimonabant
The FDA continues to review other drugs with a view toward withdrawing approval from some of them.
http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/uc...
The FDA also nudges companies to withdraw drugs on their own part.
http://www.fda.gov/Drugs/DrugSafety/ucm277114.htm
Further, the FDA recalls drugs and medical devices if particular manufacturing batches are shown to have defects.
http://www.fda.gov/safety/recalls/default.htm
The simple fact of the matter is that the FDA, like any regulatory agency in a democratic country with a free press, gets pushed from all sides. Sometimes criticism of the FDA takes the form that it is too slow to approve drugs or medical devices that are already approved in other countries. Simultaneously there is criticism that the FDA approves some drugs or medical devices without full information from the companies that make them.
I have lived in another developed country with a national health insurance system (for which I was eligible as a foreign resident with a visa that included work permission) and highly educated physicians and some central government regulation of drugs and medical devices. Sure enough, there were drugs there available by prescription that are not available in the United States, and the other way around. Each country's political system balances risk and benefits in its regulatory framework, subject to political pressures of various kinds and trumped in the end by the clinical facts of who lives or dies while taking various drugs or using various medical devices. My son the hacker spent last summer working for one of the large medical device companies in my town, and EVERYTHING about his work was stringently reviewed by the FDA, so much so that the work he completed will probably not see the market for a few more years yet.
Alex, I see you are part of that minority of HN users who joined much earlier than I did (which is what I recalled before I checked your user profile). I appreciate many of your posts. I don't know if anyone else here has told you this, but just as you see that I post in a lot of threads about medical research or medical practice regulation (because my mother was a nurse in a research hospital, and indeed was one of the first persons in the entire world to learn how to assemble and disassemble a heart-lung machine), I see that you post a lot on those issues. You appear to come to HN with a worldview that regulation of prescribed drugs has mostly failed, and medical practice in general is ineffective. And yet you also seem to have a view about controlled subtances that is not fully consistent with that point of view, because street drugs that have had no rigorous studies of safety and effectiveness (and are known to put people into hospital emergency rooms from time to time with deadly symptoms) are sometimes championed by you in other posts, while prescription drugs that have been carefully studied in that regarded are doubted in most of your posts.
I would suggest to anyone reading this that it would be more consistent to subject ALL of your beliefs to the test of evidence and to find out if ANY drug, prescribed or illicit, really provides benefit to the user, and if ANY seller of drugs, "Big Pharma" or your favorite local dealer, has any other motive in mind besides making money. The commonplace HN meme of "drugs approved by the FDA are bad," while "drugs prohibited by the DEA are good" is unlikely to be true in general on its face, and anyway has to be tested with good evidence on a case-by-case basis.