Looking back from 2012, it seems like a lifetime ago that I first stumbled on what I now call Bactrim-Septra. It was 1994 and I was still a relatively young reporter working for The Sunday Times of London, doing investigations - many in medicine. The specific assignment was to look at a giant pharmaceutical empire, known in America as Burroughs-Wellcome and in Britain as the Wellcome Foundation.

Trawling through its many drugs and research activities, I eventually came to Bactrim-Septra. Already past its peak in marketing terms, it continued to be prescribed in remarkable quantities - pretty much every time a family doctor sat down to work. Huge publicity backed it, along with promotions from pharmaceutical reps. It was a middle-of-the-road, broad-spectrum, treatment for infections. Bactrim-Septra was what they call a "blockbuster".

You'll want me to get to the key points, so I'll simply say this: I think the scandal has hidden behind the names. When I first started looking, I was focused on Septrin, which is what Wellcome marketed in Britain. Generically, it was called co-trimoxazole, and it contained two synthetic antibiotics. Quickly, I discovered that this two-in-one product was identical to Bactrim, marketed by another drug company Roche - mostly in the United States. Then up came Sulfatrim, Cotrim, Septran, Sugaprim, Ectrin, Trisulfam, TMP-SMX, TMP-SMZ, and literally dozens of others. All the same.

This was marketing, and it would create huge confusion. But the core of the drug's problem was what it was made from. Bactrim, Septra, call it what you will, contains trimethoprim and sulfamethoxazole, in the ratio of 1 to 5. That's one part trimethoprim to five parts of sulfamethoxazole. And, since two rather than one drug would seem to potentially double the risks, one of the things I tried to find out was why?

So, working for a big newspaper with a global reputation, I phoned one of the doctors who first researched the drug's effects. And I asked him, straight off, about the composition.

"Why is it that there are five parts of sulfamethoxazole to one part of trimethoprim?"

Straightway, he hung up. Slammed the phone.

After I published my first story, I think I found out why. I was deluged with letters and phone calls. Again and again, I heard the same horrifying stories, of people dying or suffering severe symptoms. And, since 2002, when I first got my website running, I've collected emails from all over the world, cataloging the side-effects of this drug.

All drugs have side effects. Even the humble aspirin. And the latex on surgeon's gloves can kill some people. But the scandal of Bactrim-Septra is that so many are preventable, and were predictable from the two-in-one formula. We found there was no reason, in almost all cases were it's used, for patients to take two drugs instead of one. And, while trimethoprim alone was safer and just as good, the addition of sulfamethoxazole dramatically raised the dangers.

My journalism looked at this, and we had some success in a campaign. Septrin was largely banned in Britain. After a parliamentary debate, government regulators moved, and trimethoprim-sulfamethoxazole was pretty much withdrawn. The only thing they said it was good for is Aids-related pneumonia, not the extraordinary number of things it was prescribed for.

But in the rest of the world, where the drug was often called something else, nobody took much notice of Britain. So with each year, month and day, I get emails coming in with yet more horror stories about Bactrim-Septra.

Most users of the drug have no problems at all. We need to keep this thing in perspective. And I'm not a doctor. I'm a newspaper reporter. I don't give medical advice. But I've heard too much not to include an important warning at the beginning of my pages of emails.

"If you have come to this website because you are unwell, and have for some reason associated your problem with a product containing sulfamethoxazole and/or trimethoprim, you should seek medical advice," I tell visitors.

"Emergency situations: Problems linked to this drug may often be minor, or long-term and/or vague, but if you are experiencing burning sensations, stinging or blisters - particularly in the eyes, mouth, genitals or rectum - fever, rash or other symptoms causing you acute concern, you should seek IMMEDIATE medical supervision, if necessary at an emergency room. Most users suffer no adverse events, and serious problems are uncommon. But, in certain unusual situations, adverse events may quickly become life-threatening and/or disabling. Your physician may not necessarily know this."

So check out the links, if you want to know more. There's also a symptom searcher to find emails from users. If you put in the drug's name and whatever it is that concerns you, then you may find others talking about the same thing. People sometimes ask me whether they will recover from their problems. In most cases, it seems like they will. This is a serious issue, however, and you probably wouldn't be reading this if you didn't have concerns of your own.

If anything here helps, or triggers you to thinking, by all means let me know. Just send me an email, and maybe it will help others. Perhaps the most we can do is warn.