top of page

Challenging Medicine's Status Quo: Sue Sisley, MD

By Edward Araujo, Managing Editor, Arizona Physician

Photography by Ben Scolaro,

Photography taken at Nectar Farms

From Print Issue - Summer 2022
  • AZP TW
  • AZP FB
  • AZP IG


Suzanne (Sue) Sisley, MD, stands tall as an undaunted fighter for what she believes in. For over 15 years, she has fought for the opportunity to research medical cannabis and other medically active plants. Whether or not medical cannabis can make the cut into more FDA-approved medicines remains to be seen, yet she fights on.

Over decades of struggles with colleagues in the medical community who are averse to change and federal agencies reluctant to fund schedule 1 drug studies, Dr. Sue Sisley has earned her integrity through her staying power through her commitment to rigorous cannabis research.

Dr. Sisley’s path to medicine started with her mother, Hanna T. Sisley, MD, a renowned Family Practice doctor focused on indigent patients in the heart of inner-city Phoenix for over 50 years. After earning her medical degree from the University of Arizona – College of Medicine, Dr. Sisley completed a combined residency in Internal Medicine & Psychiatry at Good Samaritan Regional Medical Center.

Sue then joined Hanna (and her devoted father Jack Sisley who served as their Office Manager) to supervise primary care patients for over 20 years in the only mother-daughter medical practice in Arizona.


The Journey to Medical Cannabis

A primary care physician, Dr. Sisley has devoted her career to treating military veterans, first responders, and American Indian tribal members. She’s built relationships in rural communities, championed underserved populations, and taken the path less travelled to find less addictive, more effective treatments for her patients.


Early on, she was anti-cannabis and anti-psychedelics. Dr. Sisley’s medical training taught her to focus on FDA-approved medications and avoid the dangers surrounding marijuana and fungi. She then began seeing some of her Veteran patients killing themselves. She was frustrated. Many veterans she treated were continuously describing to her how cannabis was life changing for them. Slowly, her skepticism waned as she saw firsthand how natural interventions were improving their morale, enabling those patients to be more functional and resilient.


Over time, other patients asked for treatment options that don’t contain the toxicity associated with typical pharmaceuticals. Dr. Sisley began to accept the natural medicine movement as a vital alternative. Even so, Dr. Sisley isn’t against Big Pharma, because as she states, “pharmaceuticals have an important place in our armamentarium to treat people.”



Cannabis Research

When the subject of medical cannabis comes up, most of her peers think of Dr. Sisley. She’s been a prominent spokesperson and is seeking to build evidence from randomized controlled trials. That will take some time, as most would-be researchers avoid the legal gray areas within and across state lines. Dr. Sisley seems to relish working in the gray areas.


Dr. Sisley’s home for conducting cannabis research is the Scottsdale Research Institute (SRI), LLC, a clinical trials site wholly owned by her. Also, Field to Healed Foundation, a 501(c)(3) non-profit arm of SRI, runs SRI’s operations, research, and charitable donations and is where she works as principal investigator. Largely due to Dr. Sisley’s persistence and outside pro bono legal support, SRI received a DEA Schedule 1 manufacturing license in 2021 for growing Cannabis and Psilocybin mushrooms, and recently approved for LSD. Dr. Sisley calls the C1 license their “golden ticket” to conduct research like the University of Mississippi had been doing exclusively for five decades.


Opposition to Research

There are strong opponents to cannabis research, including pharmaceutical companies, law enforcement and the federal government.


Pharma may see cannabis as a financial threat. Dr. Sisley says, “Some of my young veteran patients pick up their pain meds at the VA, sell them, and then buy cannabis with the proceeds.” Having more legal options to purchase medical marijuana directly would undercut the sales of common pain/sleep/anxiety medications.


Under the Controlled Substances Act, the federal government argues marijuana is a Schedule 1 drug, listed alongside heroin, LSD, and ecstasy, and defined as having “no currently accepted medical use and a high potential for abuse.” Moving marijuana to Schedule 2 would make investigating medical effects much easier, allowing for more government grants and greater interest among researchers.


Dr. Sisley says, “That would probably lessen the load that private donors now carry and allow for more charitable donations as they’re afraid, as well. There are well-funded foundations eager to help in Arizona but refuse because funding research into a Schedule 1 drug could jeopardize their non-profit status with the IRS.”


Overcoming Physician Fears

Dr. Sisley says her fellow physicians fear speaking with patients and their families about certifying use for qualifying conditions or being labelled a “pot” doctor. Despite marijuana being legal in Arizona, most physicians steer clear of jeopardizing their DEA registration to prescribe controlled substances.


Physicians were initially scared of retribution from state licensing boards, as they weren’t sure how the boards would react to state legalization. After the first Arizona dispensaries opened in 2012, small number of naturopathic doctors started writing marijuana certifications at an alarmingly high frequency through the Arizona Medical Marijuana Program. Reprimands of those bad actors helped to control the industry and lessen pressure on allopathic and osteopathic physicians.


Until the federal government legalizes medical marijuana use, some physicians will remain fearful and avoid certifying patients to use cannabis in its various forms.


To assuage some fears, Dr. Sisley says of the state certification program, “It’s confidential.  They can’t be tracked by the public. ADHS is not disclosing which doctors are certifying.”


Another consideration is liability. Fortunately, no suits have been filed by patients or families alleging misconduct by physicians who participate in the Arizona Medical Marijuana Program.


Although Dr. Sisley believes the state medical program is good, she fears that if more doctors don’t get involved, recreational marijuana will overrun the medical market. This could leave little room for truly sick patients to maintain their access to low-cost medical cannabis.


What’s In the Plant?

The whole cannabis plant is a complex symphony of hundreds of unique bioactive molecules interacting with each other. Dr. Sisley says, “That’s what’s amazing. We focus on the flowering tops of the plant because that’s where you find hugest density of cannabinoids and terpenes. The whole plant, even those fan leaves, the sugar leaves are loaded with cannabinoids, flavonoids, and terpenes.”


Dig a little deeper and you’ll find other useful parts. “There is a lot of evidence our ancestors doctored themself with the roots of the plant, rich in interleukins that contribute to the well-documented anti-inflammatory action of cannabis,” states Dr. Sisley.


The low-TCH version of cannabis, called hemp, is used for textiles, paper, animal bedding, insulation materials, food and feed, cosmetics, etc.



But Does It Work?

Randomized controlled trials (RCTs) have shown medical cannabis to be effective for select ailments. But not enough RCTs have been conducted especially for psychiatric conditions, insomnia, autism etc. Observational trials have provided better data, because they’re easier & cheaper to conduct than RCTs and researchers can use real-world marijuana plants that are more robust than the diluted low potency research-grade cannabis currently available from University of Mississippi.


Observational trials are less rigorous than RCTs, so they have less credibility with the medical community. Dr. Sisley says, “You’re allowing people to take what they choose. They might be taking their normal daily dose of cannabis and you’re collecting their subjective, often biased reports. It doesn’t have a placebo control. No one is blinded. The researcher knows what everyone is getting, which introduces study bias.”


Dr. Sisley and SRI are trying to change the game. Leveraging their Schedule 1 manufacturing license from the DEA, they are seeking to grow higher quality and more diverse robust plants with potency consistent with real-world flower for FDA-approved human research. Dr. Sisley and SRI design trials, grow the cannabis, receive funding from sponsors, and conduct the trials on volunteers. SRI can gift their plants to other researchers but only to scientists or organizations that also hold a Schedule 1 license.


What her research studies published in journals like The Journal of Pain, Journal of Cannabis Research, and National Library of Medicine, have shown mixed results so far. In one study, “The Short-term impact of 3 smoked cannabis preparations versus placebo on PTSD symptoms: A randomized cross-over clinical trial”, the study did not find a significant differences in change in PTSD symptoms severity between the active cannabis concentrations and placebo by the end of Stage 1 (1). Dr. Sisley attributes the low efficacy to poor quality of the government study drug. In “High-Frequency Medical Cannabis Use is Associated with Worse Pain Among Individuals with Chronic Pain,” (2) greater daily frequency of cannabis use was linked with higher pain severity. While, in “Pills to Pot: Observational Analyses of Cannabis Substitution Among Medical Cannabis Users with Chronic Pain,” (3) most users reported improved pain and health since substituting cannabis from pain medications.


What the Future Holds

Dr. Sisley doesn’t want to be characterized as a champion for medical cannabis. She says, “I’m a champion of objective data collection to hopefully uncover new medicines that are plant or even fungi-based that will serve as an alternative to toxic pharmaceuticals.” If there is any way to veer away from opioids for chronic pain, then she believes that is a victory. That includes, even if medical cannabis is never authorized as an FDA approved medicine.

She would like to persuade the FDA to change the criteria for what is medicine. “Stop forcing physicians to the Big Pharma model of medicine that uses synthetic materials – single molecule targeting one receptor in the body,” she says. Dr. Sisley believes drugs approved by the FDA, including Epidiolex (cannabidiol), Marinol (dronabinol), Syndros (dronabinol), and Cesamet (nabilone) have not been successful. She doesn’t subscribe to the current system that, she says, “you can only have one molecule targeting one receptor in the body, and that the drug must be clean and neat, precision dosed. That paradigm doesn’t always work well when it comes to complexity of natural plants and fungi. Changing the current system is a big mountain to climb, but she believes the FDA needs a new paradigm when evaluating botanical medicine.  



For over 15 plus years, Sue Sisley has made it her life’s work to challenge the status quo in medicine, medical research, and how medicine works with government, simply so that her patients can have an opportunity to get better. Her hard work maybe hasn’t brought forth the outcomes she’s looking for, yet because she fought for the opportunity to do so, she’s only at the beginning of her journey. We can all appreciate her resiliency.

Dr. Sisley Research Studies:




bottom of page