For centuries, acupuncture has been used for its pain-relieving benefits. Now, doctors are using the therapy in an unexpected setting: the operating room.

Lauren Hennessey is being prepped for surgery. Along with drugs, she's also getting acupuncture.

Duke University Medical Center anesthesiologist Dr. TJ Gan says acupuncture triggers endorphins and other natural pain killers in the body, making medication more effective.

"We have found that by using acupuncture, you can potentially reduce the amount of painkillers that you otherwise would need to use during surgery as well as in some studies suggest that acupuncture can also reduce the amount of anesthetic that you need to provide for the patients," said Gan.

Fewer drugs mean fewer side effects.

"I never vomited, I was nauseous for very shortly and my pain was very minimal," said Lauren Hennessey, acupuncture patient.

Gan says the pain relieving benefits of pre-op acupuncture may outlast the effects of any drugs.

"Not only does it benefit the patient immediately post-operatively, there is also increasing evidence to suggest that this will prevent longer-term pain problems," said Gan.

Still Gan says acupuncture should only be used as a complement to traditional anesthesia.

"For most of the conditions, I think we still need powerful drugs to control pain, but I think acupuncture would be a very useful addition to that regimen," said Gan.

Acupuncture for surgery pain is also used at Yale, Stanford and Massachusetts General.