Large packet sizes of common medications may be making us resistant to antibiotics

When we’re prescribed antibiotics, we make sure we follow the doctor’s instructions. Yes, we will take them at the same time every day. And yes, we will take them all until the packet runs out.

The last part is where many people have run into trouble. And it’s not because they want to disobey a doctor’s orders, it’s because the packet of antibiotics seems to far exceed the necessary dosage.

In Australia, the greatest amounts of antibiotics are prescribed in general practice and now it is being suggested that their over-prescription may be contributing to antibiotic resistance.

This is recognised as a serious threat, putting recovery from serious infection in doubt, and beginning to risk many therapeutic and diagnostic interventions in tertiary care requiring secure antibiotic cover – something now labelled a global threat.

Several guidelines exist in Australia to guide primary care. The Australian (electronic) Therapeutic Guidelines (eTG) are widely used; these give evidence-based recommendations on the basis of a diagnosis and tell GPs the recommended antibiotics, along with dose, frequency and – importantly – duration.

Antibiotics are almost universally packaged by manufacturers in packs with left over pills. This had researchers at the Australian and New Zealand Journal of Public Health speculate on the whether packing size matches the guideline recommendations for duration, if any mismatch might contribute to unused antibiotics in the community and, if taken by patients on some other occasion, may contribute to unprescribed use and, thereby, resistance.

The authors studied 32 common antibiotic prescribing scenarios, 10 had doses left over in surplus and 18 had a shortfall, leaving only four in which the packaging size matched the duration recommended by electronic Therapeutic Guidelines. Where there was a shortfall, this was only exactly accommodated by a repeat prescription in two cases.

This mismatch in duration between guidelines and the packaging may mean that a considerable quantity of antibiotics are dispensed and not consumed for the prescribed acute illness, contributing to redundant antibiotic doses in the community.

Curiously, it is unlikely that all primary care clinicians follow optimal guidelines in their antibiotic prescribing – this is one of the causes of antibiotic resistance – despite there being evidence-based guidelines available to combat overprescribing. But even then, if general practitioners attempt to follow guidelines, difficulties in matching diagnoses and trying to match pack size with recommendations is an obstacle.

At this point, the team at the ANZ Journal believe solutions are not obvious, though one could be changes to legislation so that the Therapeutic Goods Administration (TGA) requires manufacturers to package antibiotics in accordance with guideline recommendations. Nonetheless, some solution needs to be trialled to close off what may be another threat to antibiotic resistance in the community.

Tell us your thoughts below.