Q&A with Almut Gertrud Winterstein, RPh, PhD
Professor and Chair
Department of Pharmaceutical Outcomes and Policy
University of Florida College of Pharmacy
Pharmacy Purchasing & Products: What are the purpose and goals of the University of Florida’s (UF) Medical Marijuana Research Consortium?
Almut Gertrud Winterstein, RPh, PhD: The purpose of the consortium is to initiate research into the safety and effectiveness of using medical marijuana, allowing a better determination of its benefits and risks. The State University System of Florida Board of Governors selected the University of Florida to lead the statewide consortium, which comprises public and private universities engaged in researching medical marijuana. Patients in the state of Florida’s medical marijuana program receive their marijuana through state-sponsored dispensaries. The consortium was founded by the state with $1.5 million in recurrent funding to help evaluate the clinical outcomes of the program and guide clinical and policy decisions.1
As with any other medical treatment, providers, patients, and regulators need access to solid evidence in order to evaluate marijuana’s benefits and risks. The consortium seeks to provide research infrastructure to support evaluations of the safety, effectiveness, dosing, and routes of administration, focusing on three key initiatives1:
More information about the UF Medical Marijuana Research Consortium is available at: https://mmjoutcomes.org.
PP&P: What is the imperative for studying the safety and efficacy of medical marijuana?
Winterstein: A 2017 report from the National Academy of Sciences Institute of Medicine summarized the current state of knowledge about the safety and efficacy of marijuana.2 Put simply, medical marijuana research is necessary because very little is known about using the drug for medical purposes.
It is important to understand that although marijuana is currently being used for recreational purposes throughout much of the US, the safety and efficacy of medical marijuana have not been vetted in clinical studies. The classification of marijuana as a Schedule I substance impedes the advancement of research; few researchers have been able to obtain a license to study the drug. However, with medical marijuana use legal in 33 states and the District of Columbia,3 research into the drug’s safety and efficacy for medical use is vital.
Further encumbering our knowledge of safe marijuana use is the fact that the majority of the research currently available is based on recreational marijuana use and typically focuses on addiction issues. Conversely, the consortium is focused on studying the effects of medical marijuana on severe, debilitating illnesses, such as multiple sclerosis (MS), Parkinson’s disease, and post-traumatic stress disorder. The effects of medical marijuana among patients with severe diseases, who are oftentimes taking multiple medications that might interact with medical marijuana, are simply not known. The consortium seeks to increase the clinical understanding of marijuana, as well as how it interacts with other medications and disease conditions.
PP&P: What does the available evidence indicate regarding the most effective routes of marijuana administration?
Winterstein: At this time, the most effective routes of marijuana administration are unknown. Smoking marijuana circumvents the digestive system and produces immediate effects; however, because the exact pharmacological pathways of clinical effects are not clear, the routes that would deliver the most optimal concentration of active ingredients are not clear either.
Understanding the multiple active substances in marijuana is a first step in identifying the most effective routes of administration. New research that identifies the various substances in marijuana and their pharmacokinetic and pharmacodynamic effects will be crucial to delineating the most effective routes of administration.
PP&P: For what indications is medical marijuana effective?
Winterstein: According to the National Academies of Science Report,2 while there is conclusive or substantial evidence that marijuana is an effective treatment for some health conditions, for many others, the evidence is limited or insufficient. For example, the report highlights substantial or conclusive evidence that marijuana is effective for:
However, only limited evidence is available that marijuana is effective for:
The report concludes that additional research is needed in order to elucidate the effects of medical marijuana and highlights that little is known about its safety for treatment of any of these conditions.
PP&P: What is the role of the hospital pharmacist in managing medical marijuana?
Winterstein: Pharmacists and other health care workers should recognize that we are in the very early stages of understanding the benefits and risks of medical marijuana. It is quite possible that marijuana has a clinical purpose for multiple indications; unfortunately, at this time we know little about dosing, drug-drug interactions, effectiveness, and safety.
Safety is perhaps the most important consideration. Many questions require further study. For example:
The pharmacist should be an integral member of the committee that develops a policy and procedure for medical marijuana in the hospital setting. When a patient prescribed medical marijuana enters the hospital, how will their marijuana be managed? This is a significant concern, as medications brought from home are typically not permitted in the hospital.
Consider that pharmacists often have little knowledge of the drug-drug interactions between marijuana and other medications. Because THC metabolism shares a common pathway with a large number of other medications, marijuana is likely to interact with many other drugs. In addition, marijuana use may affect the central nervous system (CNS); this is essential information for pharmacists and patients taking other medications in combination with marijuana that affect the CNS. A broad overview of the possible interactions involving medical marijuana is available at: www.mdpi.com/resolver?pii=jcm8070989.
It is critical to understand that marijuana is a drug, and as such, must be studied in a clinical environment. Looking to the future, marijuana should be managed in the same manner as any new drug to determine its risk-benefit profile. It will be important to conduct research in order to understand its safety profile and how marijuana interacts with other drugs. We are hopeful that the UF Medical Marijuana Research Consortium’s work will elucidate some of this information.
Almut Gertrud Winterstein, RPh, PhD, is a professor and chair in the Department of Pharmaceutical Outcomes and Policy at the University of Florida College of Pharmacy. She also holds an affiliate appointment in the Department of Epidemiology at the Colleges of Medicine and Public Health and Health Professions at the University of Florida. Almut received her pharmacy degree from Friedrich Wilhelm University in Bonn, Germany, and her PhD in Pharmacoepidemiology from the Charité Humboldt University in Berlin, Germany.