Scientists have developed a bio-compatible surgical patch that releases non-opioid painkillers directly to the site of a wound for days and then dissolves. The polymer patch provides a controlled release of a drug that blocks the enzyme cyclooxygenase-2 (COX-2). This enzyme drives pain and inflammation.
The study led by scientists at Duke University is published in the Journal of Controlled Release.
Author of the paper, Matthew Becker, the Hugo L. Blomquist professor chemistry at Duke said, "We were making hernia meshes and different antimicrobial films. We thought you could potentially put pain drugs or anesthetics in the film if you just sew it in as you're stitching the person up, then you wouldn't necessarily have to prescribe any opioids."
Becker said, "Most polymers that are used in medicine swell, and everything comes out at once. The film is about like a piece of paper. If you can get four or five days of pain control out of the patch and not have to take those other pain drugs, not only do you avoid some of the side effects and risks of addiction, you're concentrating therapy where you need it."
Studies in rat showed that the painkiller stayed in tissue closer to the patch site, rather than entering into the circulating plasma.
Becker has stated that the patch will provide three or four days of wound-pain management, which is the critical period for post-surgical pain. The implantable film is useful in cases like endoscopic procedures and instances where the physicians and patients would like to avoid opioid exposure such as Cesarean births and pediatric surgeries. In mice models of neuropathic pain of diabetes, the pain patch was placed against a nerve and provided a four-day nerve block.