Edit: The first edition of this post implied that the conclusion of the scientific study cited was to use antibiotics "until you feel better." This is not the case. The relevant conclusion of the study is quote:
Clinical trials are required to determine the most effective strategies for optimising duration of antibiotic treatment
Edit 2: This does not mean you should unilaterally cut down on your course of antibiotics. Until new guidelines come out following your doctor's prescription is the only safe choice.
Almost every doctor on earth recommends finishing a course of antibiotics once you've started.
If you read the instructions that come with any antibiotic prescription, you've no doubt seen the same recommendation made there as well. If you google the question, the internet as a whole will, for the most part, give you the same resounding answer.
Ostensibly, the purpose of this long standing advice has been simple: if you stop using antibiotics when you feel better, instead of using the whole course, you may may fail to totally wipe out the invasive bacteria, and the few bacteria you left behind will now be more likely to have developed resistance to the antibiotic you used.
As the research paper from the BMJ mentions, the fear of under dosing antibiotics stems from the very early days of antibiotic treatment. From the very start there was a real fear of not giving enough antibiotics and thereby inadvertently breeding antibiotic resistant bacterial strains.
This idea is engrained in the use of antibiotics worldwide. Indeed, I have been guilty of escoriating friends and family for failing to do this.
So imagine my surprise to discover that:
For common bacterial infections no evidence exists that stopping antibiotic treatment early increases a patient’s risk of resistant infection.
You read that right, apparently this has been a quietly changing norm for some time. Even the CDC changed their antibiotic use language from supporting completion of a full antibiotic course to "use as prescribed."
So where does this leave us exactly? It would appear that common practice regarding the course of antibiotics may simply be wrong. Certainly the BMJ, which is a prestigious journal, takes an unequivocal position that "shorter treatment is clearly better for individual patients." The best advice, moving forward, is not yet clear, but the BMJ recommends further clinical study to come up with a clearer answer on what time tables make the most sense.
Info Source
http://www.bmj.com/content/358/bmj.j3418
Picture Source:
[1]Bmramon at English Wikipedia CC BY-SA 3.0 via Wikimedia Commons