Can antibiotics help improve low back pain, radicular pain (pain radiating down the leg from the lower back), or both?

Key messages

• Compared with placebo (dummy treatment), antibiotics may reduce back pain slightly and may have some beneficial effect in improving disability in the short term in people with low back pain linked to damaged vertebral endplates (the layer between the disc and the vertebra) and disc rupture. It is unclear if antibiotics increase the risk of unwanted events and serious unwanted events compared with placebo.

• We need more high-quality, long-term studies to confirm the benefits and harms of antibiotics. Future studies should explore different types of antibiotics, alternative ways to deliver them (like injections), and populations in various world regions to account for antibiotic resistance.

What are low back pain and radicular pain?

Low back pain is pain or discomfort in the area between the bottom of the ribs and the crease under the buttocks. Lumbar radicular pain, sometimes known as sciatica or radiculopathy, refers to pain that radiates down the leg from the lower back. The most common cause of radicular pain is irritation of a nerve root in the lumbar spine (the bottom five vertebrae). Low back and radicular pain can seriously limit the ability of people to work, enjoy hobbies, and stay independent.

How are low back pain and radicular pain treated?
There are many treatments available for low back pain and radicular pain, including education, self-care, painkillers, and physiotherapy. Some studies have suggested that low back pain and radicular pain may stem from an infection in a spinal disc caused by the bacteria Cutibacterium acnes (C. acnes), which is commonly found on human skin and is best known for its role in acne. For this reason, some experts think that antibiotic treatment for C. acnes (e.g. penicillin) could improve low back pain, radicular pain, or both.

What did we want to find out?

We wanted to find out if antibiotics were better than placebo (dummy treatment) or other treatments for reducing pain and back-related disability, and whether these antibiotics had any unwanted effects, in people with low back pain, radicular pain, or both.

What did we do?

We searched for studies that investigated antibiotics compared with placebo in people with low back pain, radicular pain, or both. We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes.

What did we find?

We included three studies with 402 people (mostly women); the average ages ranged between 45 years and 51 years. The studies took place in Denmark, Belgium, and Norway.

Main results

Compared with placebo, antibiotics may improve back pain slightly after 12 to 14 weeks in people with low back pain linked to disc rupture and damage to the vertebral endplate (the layer between the disc and the vertebra). Two studies measured this outcome in 255 participants. On average, people who had antibiotics rated their pain as 50.6 out of 100, compared with 59 out of 100 among those who had placebo.

Compared with placebo, antibiotics may result in a small to moderate improvement in back-related disability after 12 to 14 weeks in people with low back pain linked to disc rupture and damage to the vertebral endplate (2 studies, 255 participants). On average, people who had antibiotics rated their back-related disability as 45.2 out of 100, compared with 55.7 out of 100 among those who had placebo (2 studies, 255 participants).

We don't know if people taking antibiotics are more likely to experience any unwanted effects compared with those taking placebo (2 studies, 262 participants). In the studies, 76 out of every 100 people taking antibiotics reported having unwanted effects, compared with 49 out of 100 people taking placebo, but we are very uncertain about these results.

We don't know if people taking antibiotics are more likely to experience serious unwanted effects compared with those taking placebo (2 studies, 262 participants). In the studies, three out of every 100 people taking antibiotics reported serious unwanted effects, compared with two out of every 100 people taking placebo, but we are very uncertain about these results.

The unwanted effects reported by people taking antibiotics included abdominal pain, diarrhoea, increased flatulence or burping, rash, and fungal infection.

What are the limitations of the evidence?

We have little confidence in the evidence for the effects of antibiotics on back pain and back-related disability, and we are not confident in the evidence related to unwanted effects and serious unwanted effects. The main issues were that the results varied widely, and the studies tested only one type of antibiotic in people from a single region (Scandinavia).

How up to date is this evidence?

The evidence is current to 26 August 2025.