Hanover — The head of general surgery at Dartmouth-Hitchcock Medical Center had a remarkably simple idea not long ago: What if the department suggested that surgeons limit prescriptions of narcotic pain pills to a specific number for different kinds of operations?

The results were dramatic: The number of pills prescribed by doctors for five common outpatient surgeries dropped by 53 percent, and patients didn’t consume all the pills they were given, according to a study published in the journal Annals of Surgery.

Even veteran surgeons really had no idea how many opioids to send home with their patients, said Richard J. Barth, chief of general surgery at DHMC, who led the team that conducted the study.

“There weren’t really operation-specific guidelines out there before,” Barth said. “Doctors are very data driven, and if there are specific guidelines, people are going to follow them.”

Over-prescribing of opioids by doctors and other health care providers is widely blamed for helping to start the epidemic now gripping the nation. Nearly 180,000 people have died from overdoses of prescription narcotics since 2000 and tens of thousands more have succumbed to overdoses of heroin and fentanyl as the crisis has evolved.

In recent years, a variety of interventions have been aimed at curbing over-prescribing. Prescription drug monitoring programs, now established in every state except Missouri, ask or require prescribers to check databases that show their patients’ purchases of controlled substances, in an effort to cut down on “doctor shopping” and encourage physicians to offer fewer pills. Insurance companies have begun notifying doctors who are heavy prescribers of opioids in an attempt to bring them more in line with norms. And emergency room physicians have been making a concerted effort to send patients home with the fewest possible opioids needed to control their pain.

Few, if any, of these projects are as simple as the effort undertaken by Barth and his colleagues. To come up with recommendations to pass along to surgeons, they first surveyed people who underwent five different outpatient surgeries: partial mastectomy, partial mastectomy with a lymph node biopsy, gall bladder removal, and two different kinds of hernia repair. They discovered that the patients consumed only 28 percent of the opioids they were prescribed, and that there was a wide range in prescribing habits on the part of the doctors.

Based on the results, they suggested to surgeons, both verbally and in writing, that they limit the number of narcotic pills to five and 10 for the two breast operations and 15 for the other three. They also told patients that they would most likely be able to manage their pain with non-narcotic pain killers such as acetaminophen or nonsteroidal anti-inflammatory drugs like ibuprofen.

The goal was twofold: to prevent long-term use of the painkillers by patients and to help block diversion of the pills to illegal users, who, they said, consume as much as 71 percent of legitimately prescribed opioids.

A follow-up survey of 224 patients showed that the total number of pills prescribed dropped from 6,170 before the education initiative to 2,932 afterward, a 53 percent decline. The average difference was greatest for partial mastectomies, where the number of pills dropped from 19.8 to 5.1 for partial mastectomy and from 23.7 to 9.6 for partial mastectomy with a lymph node biopsy.

Only one patient came back for prescription refill.

“From the surgeon’s standpoint, helping people unfortunately has the side effect of causing pain, and we want to relieve patients of their pain,” Barth said. Physicians are also under pressure from satisfaction surveys conducted after procedures, which ask patients to rate how well providers managed their pain.

When the researchers surveyed 148 of the patients to determine the number of opioid pills they actually took, the numbers were equally startling. That group had been prescribed 1,913 pills but took only 656.

“Most doctors say ‘I want to take care of their pain and I don’t want them to have to come back and get a refill. So I’m going prescribe them a lot,’ ” he added.

“The problem is there is a lot of cost to society.”

The study was not set up as a randomized controlled trial and therefore cannot definitively link the results to the education effort. But Barth noted that just four of the 34 surgeons in the study wrote half of the excessive prescriptions, and those surgeons had missed the education effort.

The research team is now compiling similar data for more serious inpatient surgeries to determine whether they can curb over-prescribing when those patients are sent home to recuperate.

“I think (the idea) has potential to have a big impact,” Barth said. “This could easily be done by other general surgeons all across the country.”