UW tests new opioid to cut recovery time

Madison, Wis.

-- A new injectable pain drug being studied at the University of Wisconsin could actually help animals recover faster after surgery.

The liposome-encapsulated opioid, developed by Dr. Timothy Heath at the UW School of Pharmacy and Lisa Krugner-Hugby of the Research Animal Resources Center have provided steady, long-acting pain relief in initial studies, according to the school. If clinical trials go well, the university says the drug formulation could help animals avoid a lengthy post-surgery hospital stay. Instead, a veterinarian could administer a shot and send them home for 5 to 21 days without pain.

"We're hoping our new pain relief injections will perform as well as or better than the current standard of care, which is usually a continuous drip of fentanyl analgesic via an intravenous catheter," says Dr. Lesley Smith, a veterinary anesthesiologist at the University of Wisconsin-Madison School of Veterinary Medicine.

The new formulation would be the first extended-release product that delivers opioids. Opioids are one of the best pain relief options available, according to the school, but because they are a controlled substance, they must be administered in a hospital setting. Oral doses in animal species previously have not worked because they are metabolized in the liver before creating the desired effective blood levels.

The school's Companion Animal Fund provided initial funding for the study.