Antibiotics: take the full course!

Good science, for a change. Not woo.

In this season of ear, throat and chest infections, there is a good chance that you, or someone you know, will have been prescribed antibiotics recently.

When given antibiotics, your doctor, and your pharamcist will/should remind you to take the full course of antibiotics.

This paper just out in Molecular Cell explains why.

If you fail to take the full dose of antibioitics, or you miss a dose, you are potentially exposing the bacteria to a sub-lethal dose of antibiotic.

According to this work from Boston & Harvard Universities, sub-lethal doses of a variety of antibiotics (including Ampicilin, a popular choice for GPs to prescribe), rather than killing the bacteria, cause a stress response in the bacteria, which in turns leads to prodution of reactive oxygen species (ROS). Kohanski et al showed that this increase in ROS production can cause up to an 8-fold increase in the mutation rate in E.coli. They confirmed that ROS was the cause by treating the bacterial simultaneously with sub-lethal doses of antibiotics, and thiourea (which limits ROS production). The thiourea returned mutation rate nearly to control levels.

ROS can directly cause random damage to the bacterial genome, leading to an accumulation of mutations. ROS can also lead to the activation of SOS genes, which repair DNA – however, in doing so, they can also introduce mutations.

Taken from here. No permision given, but fair use claimed.

Some of these mutations may confer antibiotic resistance upon a bacteria. Which means your bugs may now survive the course of antibiotics.

The upshot of which is you need more antibiotics, and you may have created your very own drug resistant form of a pathogenic strain of bacteria (think MRSA).

WooHoo! Go YOU!



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