A quick google search brings up multiple articles about doctors going to jail. Here’s one where the doc got 13 years for prescribing over 1 million units[1].
We spent the better part of decade catching and locking up doctors who prescribed opioids out of guidelines, so much so that doctors are now terrified of prescribing them to people who legitimately need them.
The problem is that the prescribing guidelines, which were written by the pharmaceutical companies themselves, described a regimen that would get pretty much anyone physically addicted to their product.
So you had doctors acting in good faith, prescribing medications only when indicated and following their manufacturer's prescribing guidelines, inadvertently creating new addicts where the manufacturer's literature said there would be none.
Not only that, but we spent several decades treating chronic pain patients with opioids, such that they are completely dependent on that class of drugs to manage their condition. Only very recently have prescribing guidelines adjusted to reflect the reality that opioids are not a good treatment for chronic pain. When those pain patients are driven off of their opioid prescriptions, even if their doctor is well-meaning, some of them turn to heroin/fentanyl to manage their pain.
The guidelines are almost always on the conservative side of safe because people who died as a result of taking the medication the manufacturer recommended way turn into slam dunk lawsuits. Part of the reason the opioid problem flew under the radar is because people got hooked and weren't dying until they OD'd so it never came back to bite the manufacturer. What are the odds of another opioid type situation? What else could the FDA do with those resources?
Doctors are not researchers. Some doctors might dig deep but others go to work then go home and spend time with their families. They also have bills to pay and school loans.
I can't recall the story exactly but there was a doctor who spoke out against a popular medication. He found that it increased a chance of a heart attack I believe by over 50%. They released a small study in a journal and his existence became a living hell. Eventually, the knowledge became main stream.
I for example had a serious reaction to cipro, left me with chronic pain. This reaction is starting to become common knowledge, yet I have found a single doctor willing to put down possible side effects of cipro in my chart. People have been reporting these side effects to FDA for 15+ years, it is affecting many people but symptoms take up to 12 months to surface and doctors don't want to accept it. I have talked to number of people diagnosed with fibromyalgia for example that later realized they took cipro for UTI right before symptoms began. Plus, the FDA has been making the label more severe almost every year. The European organization EMA suggested doctors use these medication only in life threatening infections.
There is a subreddit dedicated to it @ reddit.com/r/floxies. There is a facebook page, which I honestly would not recommend, as it is really toxic.
Popping/clicking joints, and not intense pain just dull/achy. These drugs are known to cause peripheral nephropathy and tendinitis. I actually just read an interesting blog about a guy that is insanely fit, recently was given levaquin with prednisone, and continued to lift. Then, tendon in his arm snapped. He is documenting very well how his body is deteriorating and what new symptoms he is experiencing week to week. I think it would be worth posting on HN, I will send you a link when I find it.
Edit: It appears any flouroquinolone can cause these symptoms, this includes levaquin, cipro, avelox. Also, symptoms can develop after a single pill or 150 pills. It is insanely odd. Taking it with a steroid significantly increases chances of having a very negative reaction.
This is a deep question, but the simple answer is they were told repeatedly that it was safe and effective to prescribe for a lot of different ailments.
[1] https://www.dea.gov/press-releases/2019/05/13/pill-mill-doct...