Antibiotic Course Completion and Resistance: Is There a Link?

Little evidence is available to support the theory that failing to complete a prescribed antibiotic course contributes to antibiotic resistance, researchers reported in the BMJ.

According to Martin Lewelyn, PhD, from the Department of Global Health and Infection at Brighton and Sussex Medical School in the UK and colleagues, the relationship between antibiotic exposure and antibiotic resistance is unambiguous at the population level and within individual patients. Reducing unnecessary antibiotic use is therefore essential to mitigate antibiotic resistance. However, the authors stated, the idea that stopping antibiotic treatment early encourages antibiotic resistance is not supported by evidence, while taking antibiotics for longer than necessary increases the risk of resistance.

A shorter treatment course has generally been believed to be inferior. However, there is little evidence that currently recommended durations are minimums, below which patients will be at an increased risk of treatment failure. Examples of how shorter duration of treatment has been shown to reduce clinical efficacy can be seen in otitis media, in which 5 days’ treatment is associated with a lower clinical cure rate (66%) than 10 days (84%) in children younger than age 2 years.

A major component to the concept of antibiotic course rate is that it ignored the fact that patients may respond differently to the same antibiotic, according to the researchers. This is currently changing in hospital systems; however, outside the hospital patients might be best advised to stop treatment when they feel better. To avoid this, primary care facilities have developed strategies to avoid unnecessary antibiotic courses being started—for example, through enhanced communication training, point-of-care tests, and use of delayed prescriptions.

However, in secondary care, strategies to reduce overuse aim to change, or ideally stop, antibiotics 48 to 72 hours after they are started, but these are challenging to implement. Reasons for this include diagnostic uncertainty and team behavior, but patients’ and healthcare professionals’ concerns about the risks of incomplete treatment are likely to contribute.

Completing the antibiotic course has persisted because it is simple and unambiguous, despite evidence that suggests that stopping antibiotics sooner is a safe and effective way to reduce antibiotic overuse.

“Completing the course goes against one of the most fundamental and widespread medication beliefs people have, which is that we should take as little medication as necessary,” the authors stated. 

Research is still needed to determine the most appropriate simple alternative messages, such as stop when you feel better. Until then, public education about antibiotics should highlight the fact that antibiotic resistance is primarily the result of antibiotic overuse and is not prevented by completing a course, Dr Llewelyn and colleagues concluded.

Reference

Llewelyn MJ, Fitzpatrick JM, Darwin E, et al. The antibiotic course has had its day [published online July 26, 2017]. BMJ. doi: 10.1136/bmj.j3418

This article originally appeared on Clinical Advisor