UW-CTRI co-hosted the inaugural UW-Madison Cannabis Research Conference at Union South on Earth Day, April 22, 2025.
As dual use of nicotine and cannabis grows, and the state legislature considers legalization of cannabis use, UW-CTRI staff networked with other researchers, clinicians, farmers, and entrepreneurs.
The conference was organized by an interdisciplinary group of UW faculty and staff including Dr. Jesse Kaye (UW-CTRI), Dr. Shelby Ellson (College of Agriculture and Life Sciences), Cayln Ostrowski (Global Health Institute), Dr. Marianne Fairbanks (School of Human Ecology), and Dr. Lucas Richert (School of Pharmacy).
“We’re interested in conducting more research on co-use of tobacco and cannabis,” said UW-CTRI Director Dr. Hasmeena Kathuria. “We know co-use has become quite prevalent. We made many connections at the conference that may help that become a reality.”
The theme this year was, “From Seed to Society: Cultivating Connections.” Presentations and panel discussions focused on four priority topic areas: Agriculture; Health and Medicine; Business and Design; Policy and Regulation.
Cannabis Policy
First, Dane County Executive Melissa Agard welcomed attendees and spoke about her support for legalization of cannabis products to level the playing field from a regulation standpoint across states for farmers, entrepreneurs, and the safety of those who use these products. It would also bring additional tax revenue into Wisconsin, she said.
Next, Dr. Jim Mills, a published historian on cannabis, who had traveled from Scotland to present the keynote, highlighted medicinal uses of cannabidiol for kids with specific childhood seizure disorders, as well as for those adults with neuropathic pain or chemotherapy.
Health & Medicine
UW-CTRI Researcher Dr. Jesse Kaye moderated a lively panel discussion on the health effects of cannabis products and its impact on healthcare.
Or, as Kaye joked, “The Boo Hiss Panel,” which got a hearty laugh throughout the room.
Kaye led the panel through a broad range of issues, including therapeutic uses of cannabis and cannabinoids, harm reduction approaches, addiction potential and cannabis use disorder, and the challenges with accurately measuring cannabis in clinical and research settings. Panelists included:
- Heather Barkholtz, PhD, Assistant Professor, School of Pharmacy & Wisconsin State Laboratory of Hygiene.
- Michael Chen, MD, Assistant Professor (CHS), Department of Family Medicine and Community Health, UW School of Medicine and Public Health.
- Hasmeena Kathuria, MD, Director of UW Center for Tobacco Research and Intervention, Professor of Medicine, UW School of Medicine and Public Health.
- Ritu Bhatnagar, MD, Clinical Associate Professor, Department of Psychiatry, UW School of Medicine and Public Health.
Chen discussed how he was part of a medical panel of doctors in Utah who would determine when cannabis use was appropriate for medical purposes. He noted that, while some cannabis products are appropriate for certain patients, cannabis can exacerbate symptoms for other patients, such as some with anxiety and depression.
Risks from Highly Potent THC
Bhatnagar, who serves as Associate Director of Psychiatric Services at University Health Services, expressed concern for UW students who are using “dabs” or “wax,” a small wax-like form of cannabis about the size of a raisin that is smoked and can be around 80 percent THC. Like many healthcare providers nationwide, she is seeing an influx of students using these potent products ending up in emergency rooms or in states of psychosis for days or weeks.
Chen echoed that, citing research that people are 11 times more likely to have a psychotic episode if they start using potent THC products before the age of 19.
Kathuria, a pulmonologist who treated patients in Massachusetts before joining UW, said many patients were more willing to be transparent and forthright about their cannabis use because it was legal there, whereas smoking THC is generally not legal for recreational purposes in Wisconsin. She has concerns about the lack of regulation of Delta-9 synthetic products, as well as vaping and smoking cannabis due to respiratory and other potential health effects.
“We need more research on the health effects of cannabis use, and co-use of nicotine and cannabis, especially in certain patient populations,” Kathuria said. “For instance, Dr. Kaye’s research has shown that among patients with cancer, smoking cigarettes is associated with greater rates of cannabis use prior to cancer diagnosis, after diagnosis, during treatment, and after treatment. Given what we know about the harms of continued cigarette smoking after a cancer diagnosis, we need to better understand how using cannabis may influence their ability to quit cigarettes, cancer treatment, and quality of life.”
Cannabis and Driving
Barkholtz runs a lab that tests for cannabis use and how it impairs people who drive vehicles in Wisconsin. Barkholtz expressed concerns about how cannabis impairs driving for hours after use and how different products affect people differently and for varying spans of time. For example, smoking cannabis can have an almost immediate subjective effect, she said, and a false sense of being ‘ok’ to drive after use. In contrast, edibles can take awhile to kick in and so they can create a false reality and lead to overdose or dangerous driving when the products intoxicate.
She is conducting rigorous research at UW with participants who use Delta-9 THC products in a highly controlled and regulated environment and who then take simulated driving tests up to four to six hours after use. Though the study is ongoing, Barkholtz shared anecdotes of participants involved in a crash head-on into oncoming simulated cars, and afterwards claim the driving test “went all right!”
“As a driver, that’s terrifying,” she said.
Kaye said research has already shown that products available now on the market in Wisconsin have been proven to wildly misrepresent in their marketing and labeling of the ingredients that are actually in the products.
Delta-9 Products
Farmers and entrepreneurs at the event pointed out that Delta-9 THC products that are legal now (because they’re synthetic) are often way more intoxicating and dangerous than flower-based products would be if they were made legal to grow and sell. In addition, those who grow and sell hemp or other legal cannabis end up throwing away many byproducts that could have positive uses if cannabis were made legal.
Health panelists pointed out that one key to regulation could be limits on the potency of products, especially those that could get in the hands of youth.
“The conference was a dynamic, multi-disciplinary event aimed at expanding awareness, fostering knowledge exchange, and bridging gaps in cannabis research, education, and policy,” said Kaye, who was a member of the conference planning committee. “I am so grateful to all the panelists and attendees for making this inaugural event a huge success. It’s exciting to partner with and learn from researchers from all across campus who are interested in cannabis research – we’re already discussing how to expand the conference for next year!”
Several news outlets, including NBC 15 in Madison, covered the event.
Kaye presented a talk on co-use of nicotine and cannabis at the Society for Research on Nicotine and Tobacco Annual Conference in New Orleans.