No, You Don’t Have To Finish Every Course Of Antibiotics

No, You Don’t Have To Finish Every Course Of Antibiotics

Most people believe — and have been told by health professionals — that it’s essential to finish a course of antibiotics to prevent antibiotic resistance. But this advice is not only wrong, it could actually be harmful.

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The idea that you have to take all the antibiotics you’re prescribed is based on the assumption that all the bacteria causing the infection have to be killed, so the surviving minority don’t become resistant. In fact, for most otherwise healthy people, significantly reducing, but not necessarily totally eliminating, the bacteria causing the infection allows the body’s natural defences to take over and mop up the remaining few.

Some important caveats

There are some special circumstances when it’s important to kill all the bacteria — when the patient’s normal defences are damaged for any reason, for instance, or when the infection is in a site that’s relatively inaccessible to antibiotics and the white blood cells that kill bacteria. This can be in the middle of an abscess or cavity filled with pus (as in tuberculosis infection), on a foreign body, such as a prosthetic heart valve, or in dead tissue that can’t be removed (as in osteomyelitis or infection of the bone).

Obviously, stopping antibiotics before a serious infection is cured will risk a relapse. That’s what happened to Albert Alexander, the London policeman who was one of the first people to be treated with penicillin by Howard Florey in 1941.

Alexander had a terrible infection that started with a scratch on his face. He developed abscesses all over his head and had already had an eye removed, but he was dying.

Within 24 hours of being given a small dose of penicillin, his fever fell, his appetite returned and the abscesses started to heal. But when the penicillin supply ran out after five days, the infection flared up again. Alexander died four weeks later.

We now know that severe staphylococcal infection with multiple abscesses, which is what Alexander had, is a type of infection that needs antibiotic treatment for weeks to prevent relapse. But there’s a lot we still don’t know about the best way to treat some types of infection. It has recently become clear that some of the conventions around antibiotic prescribing are neither based on evidence nor harmless.

Antibiotics are generally benign but they all cause allergies and other rare side effects in a small proportion of people. And there’s a universal effect that’s less well known — even a very short course will kill many of the friendly bacteria in the gut.

The effect lasts for weeks, and the longer the antibiotic course, the greater the risk that antibiotic-resistant bacteria will take their place and cause harm. What’s more, they can spread to other people and add to the pool of antibiotic resistance in the community.

They can do worse damage too. Antibiotic-resistant bacteria include Clostridium difficile, which can be carried harmlessly in the bowel until a course of antibiotics kills off its competition. This allows it to multiply and produce toxins, potentially causing life-threatening diarrhoea.

This, in turn, increases the risk of the bug spreading to other people, especially in hospitals and nursing homes where serious outbreaks often occur. Again, the longer the antibiotic course, the greater the risk of antibiotic-associated diarrhoea.

The right dose

The rate of antibiotic resistance (in a community, a hospital or a whole country) is proportional to the total amount of antibiotics used. The relationship is complex but the dangerous increase in multidrug-resistant bacteria has led some experts to predict the “end of the antibiotic era”. This is the downside of 75 years of antibiotic therapy.

Antibiotics have saved countless millions of lives, but have been often misused because of the misguided belief that they are harmless.

The most important — but hardly novel — message for doctors is “don’t prescribe antibiotics unnecessarily, especially for colds and flu, which are nearly always viral”. Antibiotics simply don’t work in acute upper respiratory infections. We all know from experience that a cough will often last for around ten days and there’s not a lot we can do to change that.

The problem is that it’s not always obvious whether some illnesses are due to infection and whether they are bacterial — and so might need treatment — or viral. Tests might help, but the patient would have to wait for results. So the decision to treat is usually based on clinical judgement — often influenced by the patient’s anxiety and the doctor’s (in)tolerance of risk.

The challenge for doctors and patients is to weigh the risks and benefits of treatment. Unless there are compelling reasons to start immediately, we should wait for test results or to see how symptoms develop. Equally importantly, we should stop the treatment immediately if, in hindsight, the diagnosis was wrong or symptoms disappear quickly.

Some serious bacterial infections, of course, need urgent and quite prolonged treatment. How long depends on the type of infection, how serious it is, the patient’s underlying condition and response to treatment.

But recommended antibiotic courses are often arbitrary; they may reflect long-standing convention or be based on a manufacturer’s decision during an initial drug trial. Recent clinical trials show that even for some serious infections, shorter antibiotic courses can be as effective as conventional, longer ones.

The general rule is: the shorter the course, the lower the risk of side effects or resistance. More trials are needed to determine the shortest courses that can be recommended without increasing the risk of relapse. But ultimately, it will still depend on clinical judgement not arbitrary rules, conventions or package inserts.The Conversation

Lyn Gilbert is Clinical Professor in Medicine and Infectious Diseases at University of Sydney.

This article was originally published on The Conversation. Read the original article.


    • Lyn Gilbert is Clinical Professor in Medicine and Infectious Diseases at University of Sydney…

      • Be that as it may, Lyn Gilbert is still not your/our/my/his/hers doctor.

        Do you think doctors prescribe unnecessarily large doses of antibiotics for fun or something?

        • I don’t know. Do doctors prescribe antibiotics to people with viruses just because people expect to be given something?

        • I think that a specialist professor in the subject knows more about that subject than almost any MD. Do you disagree?

    • My doctor has always told me it’s important to finish a course to make sure it works as intended, not to prevent antibiotic resistance.
      So I agree, I’ll follow my Doctor.

    • While your doctor isn’t infallible (no human is), this is a sound approach.

      As detailed in comments below there is a great deal of evidence and consensus opinion applied to the prescribing of antibiotics now. The days of “hand ’em out like smarties” are no more and use is monitored. So following personalised professional advice, based on guidelines and standards, is always sensible and responsible.

      Unfortunately the title and lead-in for the article aren’t. The underlying point that Prof Gilbert was trying to make has some merit … that is, continuing courses of antibiotics where there is no benefit and only risk is not wise. But the average punter doesn’t know where the safe cut off lies and so shouldn’t be making this judgement as the title seems to advocate.

    • Always trust the doctor you can sue, rather than a random internet blogger that you can’t.

      That’s probably why the origina artice seemed to skirt around wihut making a clear recommendation, sue sue sue me.

  • I would finish the lot to make sure it has killed everything, if you only half do it you can then risk breeding and passing on antibiotic resistant bacteria.

      • Yes Professor Gilbert is an expert in infectious diseases. Probably know just a little bit more about antibiotics than your average GP.

        • The hard part is figuring out when cutting your course early is OK, since you have no easy way of knowing when it’s safe – and your doctor probably doesn’t know enough about the details of the medication to be sure when a safe cutoff falls, either.

          In other words, cutting the course prematurely may be harmless or even beneficial, but most people have no way of knowing when this is the case. Without professional advice, there’s a good chance you’re better off following the formal recommendation.

        • Probably a case of trying to disseminate this info down to the GPs as the new norm – some GPs may be working from “what my lecturer taught me” when they were a tad younger.
          Medical research is always adding new info – requiring new takes on old thinking

      • There have been few studies on this. As the very article mentions:

        “More trials are needed to determine the shortest courses that can be recommended without increasing the risk of relapse.”

        Until those are done and there is consensus I shall do what my Doctor recommends.

      • Not far off it.

        Listen to YOUR doctor, and not some random clinical professor that knows nothing about you and your particular situation. There a hundreds of thousands clinical professors in the world, you only have one doctor.

      • the problem is google for
        “course of antibiotics needs to be completed as advised by professional” even with a such a lame phrase there are tonnes of articles that come up that say the opposite and most of them from very reliable researches / med professionals

    • Kids, You should not brush your teeth lest you harm the friendly bacteria in your mouth.

      Have you taken your inner health plus today?


    • ‘Cause a Doctor trying to reach out to the community is “just” and “academic on lifehacker”. Wow

  • As a RN, I have to acknowledge the value of research and also acknowledge that methods of treatment do change. I also have to acknowledge that there are getting to be many antibiotic resistant strains of various bacteria out there (MRSA, VRE and new strains of TB among too many others). But as a health professional I also know that the vast majority of treatment courses are based on best evidence from prior practice, this is the major reason for recommended treatment courses. As for why courses last so long and you SHOULD complete a course, the simplest explanation is because you want to make sure every single bug is dead so you don’t end up re-infecting! Also killing them all helps to limit the chances of resistant bugs developing from the surviving bacteria. Please folks, research may and probably will change treatments, but until then assume that your Doctor really does know what they are talking about and they are right there aware of the whole situation, not in a laboratory in Sydney.

  • “But ultimately, it will still depend on clinical judgement not arbitrary rules, conventions or package inserts.”

    I think that’s pretty much what most commenters are saying. It’s the headline that’s wrong, not the advice in the article. So you should listen to your GP. If anything, the advice is about getting through to clinicians the need to balance competing considerations, rather than for patients to stop placing primacy on their doctor’s advice.

  • Maybe a little yogurt and probiotics would help maintain the good bacteria while the nasties are being killed off?

  • From a peer comment on the original article:

    “I’m unsure if a headline like this is entirely helpful. One can only hope that it is not picked up by media outlets that are only looking for a bit of clickbait to create some page views.”

    They are looking at you, Lifehacker.

  • In Australia, we have what is know as “The Antibiotics Therapeutic Guideline” , which experts in their particular fields sits down every so often to form a consensus on what antibiotic to use for a particular infection and for how long. When dr or pharmacist tell you to finish the course, they generally refer to the duration that experts consensus published in the current guideline.

    Note the word “consensus” because not EVERY expert agree on any particular therapy, but the majority opinion prevail. It is like the topic of vaccinating children, one or two “clinical professor” may think is it not a good idea ( they may even claim it cause autism etc), but the experts consensus still recommend vaccination.

    Your article is dangerous because it is an opinion from one “expert”.
    (… And I am a pharmacist)

    • Agree completely. The audience, including myself, are not qualified to assess this. One needs to read the original article, the trial results, and the papers that have been written. This very likely takes more time and knowledge than most of the readers of this blog can muster. The article is fine in the right context, I don’t think a blog for getting life advice is an appropriate place to be pushing views from ‘recent trials’.

          • Former surgeon and researcher, not a Professor:
            On 28 January 2010, a five-member statutory tribunal of the GMC found three dozen charges proved, including four counts of dishonesty and 12 counts involving the abuse of developmentally challenged children.[12] The panel ruled that Wakefield had “failed in his duties as a responsible consultant”, acted both against the interests of his patients, and “dishonestly and irresponsibly” in his published research.[13][14][15]

          • He was a specialist ( gastroenterologist), senior lecturer, honorary consultant at the Royal Free Hospital School of Medicine, was a fellow of the Royal College of Pathologist. He had his research paper published in The Lancet……. Not many professors has his credentials!

          • You understand (poita does, clearly) that Wakefield’s “data” were debunked as complete and utter crap, right? That’s the scientific phrase-but I’m only an Associate Professor and may have missed a more technical version.

            In 2009 Wakefield was accused of misreporting his results from his 1998 paper, which you refer to woofwoof. He is not entitled Professor, but Doctor.

            In 2010 Wakefield was found to be dishonest and that he had “failed in his duties as a responsible consultant”. He reportedly falsified data for his paper of 1998 which was subsequently decried as “utterly false” by the Editor of the journal in which it was published (the Lancet) which retracted because they had been “deceived”.

            He was struck off the UK medical register and is barred from practising medicine there.

            He was aiming to profit from “litigation driven testing” drummed up by his false claims of a link between the MMR vaccine, autism and bowel disease. Most of his co-authors even withdrew their support for that study.

            His fraud is one issue used by the modern “anti-vaxxer” movement to support false claims that vaccines are in some way dangerous to our children. Beyond the relatively rare and usually mild adverse events openly described on the packet insert, they are not a danger. They are safe. They prevent severe infectious disease which many of us now have no memory of living alongside of. Thankfully.

            The implications of avoiding childhood vaccination can include death and lifelong disability.

            Zero Professors think vaccines cause autism.

            Some references…

          • @gizmac, let me be clear, I am not questioning the merit of vaccination (vaccination save lives. Full stop). I brought it up as example of the potential danger of listening to one expert for any emerging new idea/hypothesis (in the Wakefield example: he hypothesised that MMR vaccine caused autism, based on his fraudulent research). That’s why we have Therapeutic Guidelines for many important things: including antibiotic uses- where a group of experts in their particular field examine the researches and validate theirs findings and form a consensus. If your research/hypothesis turn out to be correct (it may well be), then I am sure the therapeutic guideline committees will examine it and update their recommendation. However, to make such a headline in a site like Lifehacker (I like Lifehacker, don’t get me wrong) is irresponsible and dangerous (probably wasn’t your fault, because you were not the one who wrote the headline!).

            BTW, I was surprised by your blanket “Zero professor” assertion. In some countries (including North America, a professor just mean “a university teacher”. One of Wakefield’s role was a senior lecturer at the Royal Free Hospital School of Medicine, and hence technically he was a “university teacher”. (But this is off the topic anyway). BTW, he still believed he is innocent (may be he is delusional).

          • Haha woofwoof. Quackwatch.
            Check out the guy advocating eating rotten meat because it is predigested and therefore allows nutrients to be more efficiently taken up by the body.

  • A doctor here with a background in biochemistry and molecular biology, as TheMatrix has correctly said we are guided by the Therapeutic Guidelines as to which antibiotics to use and when – often in consultation with Infectious Disease units if there is any grey areas or concern.

    This article is correct in that antibiotic resistance IS becoming an increasingly concerning problem, however the tone of the title implies you don’t need to follow your doctors advice – WHICH IS OUTRIGHT WRONG! One of the BIGGEST problems with antibiotic use is that incomplete courses DO breed increasingly resistant strains of bacteria, which is why your doctors has always reinforced the importance of completing a course of antibiotics when indicated. Yes, historically it was ‘easier’ to give someone a short course of amoxycillin for a viral respiratory tract infection mainly because patients demanded *something* to make them feel better rather than try to convince them the truth that they didn’t need them, but this practice has long since been stamped out (in the area I work in at least). My fear with this article is that it encourages those who would continue the practice of finishing courses BEFORE indicated by the doctors instructions – and I can’t help but wonder if this article is somehow taken out of context from a larger piece? There is a LOT of VITAL information simply missing, in my opinion.

    • Could you point me to some literature on the development of resistant microbes due to failure to complete a prescribed course of antibiotics?

    • And I note with interest that in the more recent versions of the therapeutic guideline they have cut down the course of trimethoprim for an uncomplicated UTI from 7 days to 3.
      There’s also the argument as well that by completing the course of antibiotics long after symptoms (and presumably the infection) have gone, you are then unnecessarily exposing the bacteria in your body to antibiotics and ironically encouraging resistance. Not to mention the potential that if someone has been incorrectly given antibiotics for a viral infection, they’ll at least limit unnecessary antibiotic use.

      • Duration and specific antibiotic for a particular infection changes as more available clinical/ researched evidences emerge. BTW, uncomplicated UTI for non pregnant women is trimethoprim 1 daily for 3 days, but for men is 1 daily for 7 days, in the latest edition of TG.

        My main point is, if you are given 3 tablets of trimethoprim and told to finish the course, the title of the article seem to suggest that it is ok to just take 1 or 2 tablets, rather than the prescribed 3 tablets ( or 7 tablets if you are a man with uncomplicated UTI)…lol

        • My point then being that *potentially* antibiotic courses are/have been longer than necessary. Certainly more research needs to be done before the practice should be adopted universally but I wouldn’t be too surprised if we one day see antibiotics being advised to be stopped as symptoms subside.

          At the very least I don’t think we should outright dismiss the idea just because it runs counter to the current paradigm in Medicine. If we strictly follow what has been established and don’t consider new ideas, doctors wouldn’t be washing their hands and we’d still be chugging down PPIs for stomach ulcers.

  • So after reading all this, the best advice is to listen to your doctor as each infection is different and requires different treatments.

  • The article should also mention that as the tiny stocks of Penicillin dwindled, the doctors tried desperately to keep Albert Alexander alive by extracting it from his urine.

  • Is it really a lesser known fact that antibiotics kill bacteria… In your gut? I came across that fact before hearing about the pedagogy of completing a full antibiotic course to wipe out selectively resistant strains. Same/same.

    You could always just duke it out, survival of the fittest and all that jazz.

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