Study Show Antibiotics Don’t Relieve Chronic Lower Back Pain

By Crystal Lindell

Antibiotics are not an effective treatment for chronic lower back pain caused by bulging herniated discs, according to a small new study by researchers in Australia.

That may sound like a “Well, duhhh” finding, but some patients with back pain are actually being treated with antibiotics.

“Antibiotics are currently being recommended for chronic low back pain, particularly when treatments have failed, even though the evidence for their use is conflicting,” writes lead author Flavia Cicuttini, PhD, School of Public Health and Preventive Medicine at Monash University. 

Low levels of bacteria have been found in the spines of people suffering lower back pain from bulging discs, and some previous studies have found that antibiotics have a “substantial effect” in relieving their pain.

One such study in 2013 estimated that up to 40% of patients with chronic back pain could benefit from antibiotic treatment. That research created a bit of a frenzy in the media, with a prominent UK surgeon saying the discovery was “the stuff of Nobel Prizes” and predicting “this is going to require us to rewrite the textbooks.”    

Now, more than a decade later, the new study seems to disprove that theory.

Monash researchers set up a clinical trial with 170 adults, all of whom had chronic low back pain (LBP) caused by disc herniation that was confirmed with an MRI. Half the participants were randomly assigned to receive the antibiotic amoxicillin twice per day for 90 days, while the other half received a placebo.

Their findings, published in JAMA Network Open, show that amoxicillin did not result in greater pain reduction than treatment with a placebo.

“Our results do not support the findings of previous studies,” wrote Cicuttini. “These findings suggest that antibiotics should not be used in the management of chronic low back pain and provide important data to prevent their inappropriate and harmful use.

“Although the potential for antibiotics to be an effective treatment has been an appealing prospect, the results of this trial do not support this hypothesis. These findings are important in informing updates of clinical practice guidelines for LBP, which to date have been unable to make recommendations for or against the use of antibiotics.”

Not only was the antibiotic ineffective, it caused more side effects. Over 16% of people who received amoxicillin stopped taking it due to adverse events, compared to about 2% in the placebo group.  

The overuse of antibiotics is actually an emerging problem in medicine, due to some strains of bacteria developing resistance to antibiotics. The World Health Organization considers antibiotic resistance to be a global health threat, with about 5 million deaths per year associated with drug-resistant bacteria.