The widely prescribed pain drug pregabalin (brand name: Lyrica) may be no better than a placebo when it comes to treating the back and leg pain known as sciatica, a new clinical trial suggests.

The study, published March 22 in the New England Journal of Medicine, found that sciatica patients improved to the same degree whether they were given pregabalin or placebo capsules.

Sciatica refers to pain that radiates along the sciatic nerve, which branches from the low back through the hips and down each leg, according to the U.S. National Institutes of Health. The pain typically shoots down the back of the leg, and some people also have numbness, tingling or muscle weakness.

The problem is caused by compression of the sciatic nerve — possibly from a herniated spinal disc.

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Pregabalin is prescribed to treat various forms of nerve-related pain. In the United States, it’s officially approved for nerve pain related to diabetes or shingles, and certain other conditions.

Doctors also commonly prescribe pregabalin for sciatica. But the new study calls that practice into question.

“We do not recommend the use of pregabalin in people with sciatica,” said researcher Christine Lin, of the George Institute for Global Health and the University of Sydney in Australia.

Not everyone agreed, however.

Dr. Houman Danesh is director of integrative pain management at Mount Sinai Hospital in New York City. He said doctors should “be aware” of the study findings. But he was not ready to dismiss pregabalin as a sciatica option.

Most of the study patients had “acute” sciatica — which means they’d had symptoms for less than three months. Most people in the acute phase will, fortunately, improve with time.

“So these are the patients who are probably on their way to getting better anyway,” Danesh said.

It might be better, he said, to focus on patients who don’t improve and progress to chronic sciatica.

The study’s findings are based on more than 200 sciatica patients who were randomly assigned to take either pregabalin or placebo capsules for up to eight weeks. The starting dose of pregabalin was 150 milligrams per day. That dose was adjusted up to 600 mg daily, the study said.

At the outset, the intensity of their leg pain was just over a 6, on a scale of 0 to 10. That’s “severe” pain, Lin said.

At the end of the eight-week treatment period, patients in both groups were faring better. The average pain score in the placebo group had dipped to 3.1, versus 3.7 among pregabalin patients — a difference that was not statistically meaningful.

After one year, their pain was still hovering around a 3.

Pregabalin patients did, however, have more side effects while they were taking the drug. The main problem was dizziness, which affected 40 percent of people taking the drug.

What does it all mean for sciatica patients?

According to Lin, people who are already on pregabalin should talk to their doctor about what to do next.

“It is important that they don’t take themselves off pregabalin,” Lin said, “because they may need to come off the medicine gradually, and under their doctor’s care.”

Stopping pregabalin abruptly can cause seizures, Danesh explained. He suggested that if patients want to try a pregabalin “holiday,” they should first talk to their doctor. If their pain returns, they can go back on the drug.

There are some other options for sciatica, according to Dr. Nadine Attal, of the University of Versailles-Saint-Quentin in France.

In the acute phase, common painkillers (such as ibuprofen or naproxen) might help, said Attal, who wrote an editorial published with the study.

Some people get relief from injections of anti-inflammatory corticosteroids, she added.

Chronic sciatica is a tougher challenge, Attal noted. She said certain antidepressants and anti-seizure medications have been shown to ease nerve pain, and may be recommended for chronic sciatica.

But the truth is, no single measure — other than time — seems widely effective for sciatica, according to Lin.

While steroid injections can help, Lin noted, they typically have a “small and short-term effect.” And research has failed to show benefits from physical therapy, she said.

The most extensive approach — surgery — may help “carefully selected patients,” according to Lin. But even then, she said, surgery serves to speed the recovery process: At the one-year mark, sciatica patients who have surgery are typically faring the same as those who opt for other routes.

The real world is, however, different from a clinical trial, Danesh pointed out. Doctors often prescribe combination treatments for chronic sciatica, he said — such as lower-dose pregabalin with an antidepressant.

Patients might also try non-drug approaches, such as acupuncture, according to Danesh. “I think it’s important that patients are aware of all the options,” he said.

Lin also offered some self-care tips: Stay as active as possible and avoid prolonged bed rest. People can talk to their doctor for specific advice on being active.