Temple University School of Pharmacy (TUSP) researchers have published new findings in Drug and Alcohol Dependence (Volume 283) on the pharmacological interactions between fentanyl and xylazine – a combination that has emerged as an urgent threat in the ongoing opioid crisis.

The research was led by Dr. Ellen Walker, professor and chair of the Department of Pharmaceutical Sciences at TUSP, with contributions from a collaboration of Temple students:

• Mariah Nguyen, B.S. , a 2023 participant in the Temple University undergraduate BRIDGE program
• PharmD graduate Kerim Cakir '25, now completing a PGY1 residency at Thomas Jefferson University Hospital
• Brandon J. Sheperd, a doctoral student in the pharmaceutical sciences program.

"Our work in the paper shows interactions between fentanyl and a common adulterant, xylazine," said Sheperd. "This was a great, collaborative team to be a part of with members at various stages of training and from different programs across the university."

Cakir echoed that sentiment, noting the value of the team's diversity: "This was a unique experience in which there were different perspectives given from a PhD student, a PharmD student, and an undergraduate student which all came together cohesively under an outstanding and highly experienced pharmacologist."

Xylazine, a veterinary sedative not approved for human use, has become increasingly common in the illicit fentanyl supply, particularly in Philadelphia. The team's research analyzed the pharmacological interactions between the two substances, finding that xylazine extends the effects of fentanyl even after fentanyl itself would normally wear off.

For Nguyen, the experience exemplified what undergraduate research at Temple can be.

"I couldn't have asked for a better undergraduate research experience than the Walker lab," she said. "All of my superiors valued collaboration to foster a conducive environment that sought to navigate the nuances of fentanyl, xylazine, and its combinations."

The article is available online at https://authors.elsevier.com/a/1ms2I1LiD3PCjY.