Are current antibiotic courses too long?
Originally published on AJP
Shorter courses of antibiotics are nearly always as effective as longer ones for many common infections, Australian experts say
Shorter durations of antibiotics can reduce adverse effects associated with their use, including resistance, according to Canberra infectious diseases physician and microbiologist Heather Wilson and co-authors in this month’s issue of the NPS MedicineWise publication Australian Prescriber.
Evidence also shows short courses are as effective as standard ones for the most common infections.
“Traditionally, the idea has been that prescribers should give a long enough course of an antibiotic to clear up an infection and prevent recurrence. However current scientific evidence doesn’t support this approach anymore,” says Dr Wilson.
“The more antibiotics are used, the greater the risk of adverse events, including resistance,” she says.
In 2015, 30% of all patients attending a general practice received an antibiotic prescription, often in quantities several-fold more than recommended by Australian guidelines.
Antibiotics don’t work for viral infections and even when the infection is bacterial, the benefits of antibiotics can be modest and outweighed by the harm from adverse effects, say the researchers.
For instance, they are not necessary for many acute respiratory infections including acute rhinosinusitis, acute sore throat and acute otitis media.
“It is important to tailor the antibiotic choice, dose and duration to the condition at hand,” says Dr Wilson.
“For an acute sinus infection, a 5-day antibiotic course is as effective as a 6-10 day one.
“Similarly, shorter courses for acute otitis media, mild community-acquired pneumonia, acute uncomplicated urinary tract infection and others are recommended.
“Using antibiotics for the correct amount of time, even if it means not finishing a complete box, and not using unnecessary repeat scripts, can also reduce antibiotic use,” she says.
While it can be difficult to differentiate a trivial from a potentially serious infection, one option is to ‘watch and wait’ and ask patients to return if there is clinical deterioration.
An alternative is to prescribe an antibiotic but advise the patient to not have it dispensed unless specific symptoms occur.
In the setting of acute respiratory infection, this has been shown to reduce antibiotic use by 50% with no significant decrease in patient satisfaction, and importantly no increase in complication rates, say the authors.
When antibiotics are prescribed, the duration (or number of tablets) should be written on the prescription, they add.
This should enable the pharmacist to supply only the number of tablets or capsules required (even if it means breaking the antibiotic pack) which avoids excessive antibiotic use.
“Repeat scripts are almost never required and we recommend changing the default setting to ‘no repeats’ in electronic prescribing software when technically feasible.”
Treasure McGuire, assistant director of pharmacy at Mater Health Services, Brisbane, and senior pharmacy lecturer at the University of Queensland, writes in an accompanying editorial that equivalence trials are needed to determine the optimal minimum antibiotic regimen for common infections in Australia.
“It is clear that no ‘one size fits all’ for the length of an antibiotic course,” says Dr McGuire in Australian Prescriber.
“Judicious antibiotic use needs to balance prescribing for too short a period (causing treatment failure, delayed return to health or the development of complications) with overprescribing which increases the risk of resistance, non-adherence, adverse effects and cost. Sub-therapeutic antibiotic concentrations can encourage antibiotic-resistant bacteria,” she says.
Dr McGuire also points out that pack size heavily influences duration of use, and “will continue to do so while consumers are given advice to ‘complete the antibiotic course’.
“We must be willing to try strategies to reduce the mismatch between guidelines and antibiotic packaging,” she says.
“Patients should be empowered to stop their antibiotic after a specified minimum number of days or when they feel better (whichever comes first) and to return any unused doses for safe disposal to the pharmacy where the medicine was dispensed.”