If you have an infection that won't go away, your doctor usually prescribes an antibiotic with instructions to finish off the course.
However, after waiting a few days you may start to feel better and wonder, what now?
According to a new opinion piece published in the British Medical Journal, people should be careful when it comes to building antibiotic resistance.
Meaning our bodies may get used to antibiotics until they stop working.
The BBC reports the team of British researchers believe the old 'finish the bottle' mantra is based on outdated data.
That resistance only happens when antibiotics are taken for longer than necessary.
These researchers say there's evidence that even short courses of antibiotics such as the ones taken for three to five days can also lead to resistance.
Critics argue that this message is confusing and won't help patients.
Instead, more research is needed before doctors can make claims about finishing or not finishing a treatment when symptoms start to ease up.
Both sides agree on one thing; the study is good for opening up a debate.
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