Researchers have found that anticonvulsant drugs that commonly treat back pain are effective and might be harmful. Photo by Africa Studio/Shutterstock

July 3 (UPI) -- Anticonvulsant drugs that are commonly prescribed to treat back pain are not effective and might be harmful, according to a new study.

Researchers led by the University of Sydney analyzed nine placebo-controlled randomized trials that showed a lack of benefit from anticonvulsants, also known as gabapentinoids, and that they could instead cause adverse reactions. The findings were published Monday in the Canadian Medical Association Journal.


"We have shown, with mostly high-and moderate-quality evidence, that common anticonvulsants are ineffective for chronic low back pain and lumbar radicular pain and are accompanied by increased risk of adverse events such as drowsiness or dizziness," Christine Lin, an associate professor at the University of Sydney, said in a press release. "There are also reports of suicidal ideation and misuse of these drugs."

The researchers noted that use of the drugs -- including gabapentin, pregabalin and topiramate -- increased 535 percent in 10 years despite limited research supporting the usage.

For back pain, clinical guidelines in the Unitied States, Britain and Australia recommend nonpharmacologic interventions and nonopioid analgesics rather than stronger analgesics such as anticonvulsants.

Anticonvulsant medications have been prescribed to treat seizures, bipolar and borderline personality disorders, and neuropathic pain, according to the Centers for Medicare & Medicaid Services.

The trials compared the anticonvulsants to placebo in 859 unique participants. Fourteen of 15 comparisons found anticonvulsants ineffective to reduce pain or disability in low back or lumbar radicular pain.

The average age of participants in each group was just under 51 years old.