Antibiotics not supported for treating chronic low back pain with disc herniation

Antibiotics seem to do nothing in terms of reducing pain in patients with chronic low back pain and disc herniation, a study has shown.

The study included 70 adults (mean age 44.4 years, 59.4 percent male) with chronic low back pain and the presence of a disc herniation on MRI. These patients were randomly assigned to receive amoxicillin-clavulanate 500/125 mg (n=85) or identical placebo (n=85). Treatment was administered twice per day for 90 days.

Pain intensity, the primary outcome, was assessed using the Low Back Pain Rating Scale (score range, 0-10, with 0 indicating no pain and 10 indicating worst pain imaginable) at 12 months. A total of 152 patients (89.4 percent) provided primary outcome data at 12 months.

Compared with placebo, amoxicillin-clavulanate was not associated with greater pain reduction at 12 months (adjusted difference, 0.06, 95 percent confidence interval [CI], −0.58 to 0.70) or 3 months (adjusted difference, 0.34, 95 percent CI, −0.18 to 0.86), independent of baseline pain.

Adverse events occurred in 40 percent of patients treated with amoxicillin-clavulanate and in 23.5 percent of those who received placebo. One patient in each group had a serious adverse event that was deemed potentially related to the intervention.

Prespecified subgroup analyses showed no differences in pain between the two treatment groups among patients with Modic changes (bone changes detected on MRI).

The findings do not support the use of antibiotics in the management of chronic low back pain and provide evidence to prevent their inappropriate and harmful use.