As Ben Goldacre says, "The people you should have been able to trust to fix these problems have failed you." The basic scenario at work in the pharmacy industry today is that the fox is in charge of the hen house. Drugs are being tested by the company that manufactures them, and their drug trials are - predictably - poorly designed, small, and hopelessly biased.
The industry scandal: drugs don't work
The Guardian blows the lid off the story.
As a result, negative data is buried, small positive results are trumpeted, and new drugs are brought to market that are worse than placebos. Worse because they don't work any better than placebos, but they can have strong and damaging side effects, not to mention the cost and inconvenience.
And as a side effect of the way the pharmaceutical industry works, there are a lot of medical problems which (as Goldacre points out) are left unaddressed because no one can make money off them.
Let's say there is a lot of evidence that vitamin C can cure an imaginary ailment I'll call Polkadotism. Sufferers of Polkadotism are left with crippling polka dot spots all over their bodies. But the pharmaceutical industry can't make money off marketing vitamin C, so they don't perform any trials. Without any trials having been performed, doctors can't recommend vitamin C therapy. And so this simple and safe form of treatment goes unexplored.
Many people with Polkadotism have probably never even heard of the possibility. Others might take massive doses of vitamin C, trying to cure themselves, and only make themselves sicker. It's a disaster for everyone but the pharmaceutical companies, who sail blithely along, unconcerned by niggling annoyances like human suffering.
Study after study has shown that pharmaceutical trials are biased loads of BS. And over and over we have situations where a drug is prescribed, only to later learn that it's not helpful. Take the example of hormone replacement therapy (HRT) for menopause. This was the standard procedure for years, until it was recently discovered that HRT hugely increases your cancer risk, and doesn't actually help with menopause.
The obvious solution is that a truly neutral third party needs to be in charge of conducting drug trials. I don't know how you can have such a neutral third party, given the staggering amounts of money the pharmaceutical industry is willing to throw around. This agency would have to be kept sequestered better than the jury at a mob boss's trial. But short of that, we simply can't trust anything that the pharmaceutical industry tries to sell us.