LULU GARCIA-NAVARRO, HOST:
Anyone who has taken antibiotics knows that when you get a prescription, you also get a warning from your doctor - take the full course, even if you start to feel better. But that advice may be wrong or at least not grounded in science. Some doctors are pushing back against the idea. And this week doctors in the U.K. explained why in an opinion piece in the peer reviewed British Medical Journal. Tim Peto was among them. He's a clinician and a professor of infectious diseases at the University of Oxford. And he joins us on the line from Oxford. This upends everything we've been told about antibiotics. Can you explain your thinking here?
TIM PETO: Well, we've been worrying about anti - emergence of antibiotic resistance. And the main reason why bacteria get resistance to antibiotics is because they're exposed to antibiotics in the community. So world wide, we think that the more antibiotics are given to the world, both to animals and to humans, the more likely the bacteria ought to get resistance. That seems common sense. However, we've also been told that you must finish your course of antibiotics to avoid resistance, which is the opposite.
That means the more you take, somehow or other, that seems to protect you against resistance. And we found this idea quite difficult to understand. So what we wanted to find out was, where did the idea come from? And we started doing some medical history going back and back in the books and eventually discovered that this came first over 70 years ago from a speech made by Alexander Fleming. He's the man who first discovered penicillin. And he got a Nobel Prize. And in his Nobel Prize speech, he made the comment that we should finish the course. That was back in 1945 in a different world. And surprisingly, that comment has taken root in our society.
GARCIA-NAVARRO: So it's folk wisdom, essentially, and not rooted in any kind of scientific proof?
PETO: Yes, that's our belief. It's folk wisdom, well put.
GARCIA-NAVARRO: So for our patients who may be listening to this, what do you think is the best medical practice now?
PETO: I think that - I think we should always say that patients should follow their physician's advice. But I think what we're saying is we can empower physicians to advise shorter courses of treatment depending on what's wrong with you. And also, if you respond well to your treatment and get better, they might well say you can cut short your course of antibiotics.
GARCIA-NAVARRO: Why haven't there been studies on this before now? I mean, why just take something that Alexander Fleming said so long ago as fact?
PETO: I suspect that for many, many years, antibodies worked brilliantly. Infections have been really solved. And it didn't really matter very much how long you took your antibodies because they were - you got better, and it wasn't important. We are now worrying about resistance emerging. And so we now want to think much more carefully about how best to use the antibiotics we got so that they don't lose their activity.
GARCIA-NAVARRO: I have a personal query about something else that we're always told - that we're not supposed to drink when we're taking antibiotics. Is that something that is also a folk wisdom or is there some scientific fact in that?
PETO: There are one or two antibiotics where they interact with alcohol. And they're not many of them. And by far, the majority of antibiotics that are prescribed have no interaction with alcohol. However, as a physician, I can never - you can never get me to say it's good to take alcohol. That's not what we're paid to do.
GARCIA-NAVARRO: (Laughter) Indeed. Tim Peto, professor of infectious diseases at Oxford University, thank you so much for joining us.
PETO: Thank you.
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