Cannabis


Kruger, D.J., Bone, C.B., Meacham, M.C., Klein, C., & Kruger, J. S. (in press). THC-O-acetate: Scarce evidence for a psychedelic cannabinoid. Journal of Psychoactive Drugs.

There is a growing interest in semi-synthetic cannabinoids, including THC-O-acetate (THC-Oac). Some cannabis marketers and users have claimed that THC-Oac produces psychedelic effects; the current study is the first to examine this claim. Researchers developed an online survey for THC-Oac consumers based on previous cannabis and psychedelic use surveys and in consultation with the moderator of an online forum. The survey assessed the experiential profile of THC-Oac and included items from the Mystical Experience Questionnaire (MEQ), an instrument for assessing psychedelic experiences. Participants reported a little to moderate level of cognitive distortions (altered sense of time, difficulties concentrating, difficulties with short-term memory) and few visuals or hallucinations. Participants' responses were significantly below the threshold for a complete mystical experience on all four MEQ dimensions. Participants who had used classic (5-HT2A agonist) psychedelics had lower scores on all MEQ dimensions. When asked directly, 79% responded that using THC-Oac is “not at all” or “a little” of a psychedelic experience. Some reports of psychedelic experiences may be due to expectations or contaminants. Those having prior experience with classic psychedelics had lower ratings of mystical experiences.


Bone, C.B., Klein, C., Munger, K., Strongin, R.M., Kruger, D.J., Meacham, M.C., & Kruger, J. S. (in press). Reviewing the risk of ketene formation in dabbing and vaping THC-O-acetate. Cannabis and Cannabinoid Research.

Introduction: In the wake of continued consumer demand despite increasing regulatory scrutiny, there is a need to develop systematic methods for identifying the harm profile of new psychoactive substances derived from hemp. THC-O-acetate, colloquially known as THCO, is the acetate ester of the principal psychoactive compound in cannabis. The heating of THCO can create ketene gas, which is harmful to the lungs.

Methods: The research team used a multidisciplinary, iterative process to develop a survey to incorporate consumers' perspectives of semi-synthetic cannabinoids. The survey was then distributed across the social media platform Reddit to learn about delivery device preferences and associated use styles when consuming THCO.

Results: Most participants (74.9%) vaped THCO and one-quarter of participants (24.3%) dabbed THCO and tended to report higher temperatures for dabbing than vaping THCO. A small portion (12.0%) of participants reported concerns regarding ketene risk.

Conclusion: The rates of vaping and dabbing THCO and the range of temperatures identified in this survey indicate an operational risk associated with consuming these substances. Further studies are needed to understand the how various routes of administration and delivery devices used with THCO may exacerbate the risk of ketene formation and other potential harms.


Kruger, D.J., Gerlach, J., Kruger, J.S., Mokbel, M.M., Clauw, D.J., & Boehnke, K.F. (In Press). Physicians’ attitudes and practices regarding Cannabis and recommending medical Cannabis use. Cannabis and Cannabinoid Research.

Introduction: Medical cannabis users tend not to trust or rely on health care providers regarding cannabis advice. Previous surveys of physicians have focused on favorability toward medical cannabis. The current study assesses how physicians interact with patients regarding cannabis in their day-to-day practice, and whether and how they address important topics such as use patterns and substituting cannabis for medications. We predicted that physicians would generally perceive cannabis dispensary staff and caretakers as not competent in addressing patient health needs and would not be likely to use their recommendations.

Methods: Physicians in a university-affiliated health system completed an anonymous online survey. The survey assessed physicians' cannabis related education experiences, perceptions of their knowledge of and competence regarding medical cannabis, and the content of cannabis related discussions with patients. We also examined perceptions of the sources of influence on patients regarding cannabis and physicians' attitudes toward medical cannabis dispensary staff and medical cannabis caregivers (MCCs).

Results: A few physicians (10%) had ever signed a medical cannabis authorization form for their patients, consistent with their perceptions of low knowledge and competence in this area. Discussions on cannabis primarily focus on risks (63%) rather than dosage (6%) and harm reduction (25%). Physicians see their influence on patients as weak compared with other information sources and have generally unfavorable attitudes toward medical cannabis dispensary staff and MCCs.

Conclusion: Greater integration of medical cannabis knowledge is needed at all levels of medical and clinical education to address the potential harm to patients if they receive no guidance. Continued research is needed to provide a strong scientific basis for developing treatment guidelines and standardized medical education for medical cannabis use.


Boehnke, K.F., Martel, M.O., Smith, T., He, Y., Bergmans, R.S., Kruger, D.J., Andwele, M., Bevan, S., Williams, D.A., & Fitzcharles, M.F. (in press). Medicinal Cannabis use for rheumatic conditions in the United States vs. Canada: Rationale for use and patient-physician Interactions. ACR Open Rheumatology.

Objectives. Understanding how medical cannabis (MC) use is integrated into medical practice for rheumatic disease management is essential. We characterized rationale for MC use, patient-physician interactions around MC, and MC use patterns among people with rheumatic conditions in the US and Canada.

Methods. We surveyed 3,406 participants with rheumatic conditions in the US and Canada, with N = 1,727 completing the survey (50.7% response rate). We assessed disclosure of MC use to and MC authorization by physicians, MC use patterns, and investigated factors associated with MC disclosure to physicians in the US vs. Canada.

Results. Overall, 54.9% of US respondents and 78.0% of Canadians reported past or current MC use, typically due to inadequate symptom relief from other medications. Compared to those in Canada, fewer US participants obtained MC licenses, disclosed MC use to their physician, or asked advice on how to use MC (all p-values <0.001). Overall, 47.4% of Canadian vs. 28.2% of US participants rated their medical professional as their most trusted information source. MC legality in state of residence was associated with 2.49 greater odds of disclosing MC use to physicians [95% CI: (1.49, 4.16), p-value: <0.001)] in the US, whereas there were no factors associated with MC disclosure in Canada. Our study is limited by our convenience sampling strategy and cross-sectional design.

Conclusions. Despite widespread availability, MC is poorly integrated into rheumatic disease care, with most patients self-directing use with minimal or no clinical oversight. Concerted efforts to integrate MC into education and clinical policy is critical.


Kruger, D.J., Karahmet, A., Kaplan, S.M., Redfield, J., Stacy, T., Agarwal, V., Faqqouseh, M., & Bone, C.B. (2023). Social media discussions on THC-O-acetate: A content analysis. Cannabis.

Novel cannabinoids require systematic research to inform policies and practices. There is a growing interest in semi-synthetic cannabinoids by consumers, manufacturers, and regulators. However, there is a scarcity of research on these substances. Online discussion forums can provide guidance for research questions when current knowledge is scarce. The current project investigates the topics and issues covered in a social media forum devoted to THC-O-acetate (THCO), a semi-synthetic cannabinoid with rapidly rising popularity. Reddit comments posted on the THCO subreddit from June 2021 through November 2021 were coded for major and minor themes by a team of five coders and a supervisor. Major themes were established and clarified through group discussions. A second round of coding confirmed major themes and identified minor themes. The analysis identified several future research topics for THC-O-acetate, including the extent of variation in product composition, the characteristics of user experiences and comparisons with other substances, whether THC-O-acetate produces psychedelic effects, concerns and adverse experiences, and user harm reduction practices. As an acetate ester, THC-O-acetate may break down when heated and release toxic ketene gas. Although several users expressed safety concerns regarding THC-O-acetate, some explicitly mentioning ketene risk, the most common administration method reported was heated inhalation.


Allard, N.C., Kruger, J.S., & Kruger, D.J. (2022). Cannabis advertising policies in the United States: State-level variation and comparison with Canada. Cannabis and Cannabinoid Research.

Objective: To assess the regulations on Cannabis advertising across U.S. states for variation and compare with Canadian federal policies, for the purpose of identifying opportunities to protect the public, especially the youth and other vulnerable populations, from health risks.

Methods: We reviewed Health Canada's Cannabis Act and Cannabis Regulations to identify prohibited marketing and advertising activities for cannabis products. The Canadian guidelines (where cannabis is legal for both medical and nonmedical use) were compared with regulations in the 36 U.S. states where cannabis is legalized for medical and/or adult (e.g., recreational) use.

Results: Cannabis advertising regulations vary greatly and have little consistency across the U.S. states. Most states do not address many of the cannabis advertising activities that are prohibited in Canada. Among the 31 states that do allow some form of cannabis advertising, 74% explicitly prohibit targeting or appealing to minors and 68% prohibit making false or misleading claims. There are 11 illegal advertising tactics in Canada, such as glamorization and testimonials, that were not specifically discussed in any of the U.S. state policies.

Conclusion: The lack of consistent marketing guidelines could expose youth and vulnerable populations to cannabis advertisements; more widespread or federal guidance is needed.


Holman, A., Kruger, D.J., Lucas, P., Ong, K., Bergmans, R.S., Boehnke, K.F. (2022). Healthcare provider and medical cannabis patient communication regarding referral and medication substitution: The Canadian context. Journal of Cannabis Research, 4, 32.

Background: Patients use medical cannabis for a wide array of illnesses and symptoms, and many substitute cannabis for pharmaceuticals. This substitution often occurs without physician oversight, raising patient safety concerns. We aimed to characterize substitution and doctor-patient communication patterns in Canada, where there is a mature market and national regulatory system for medical cannabis.

Methods: We conducted an anonymous, cross-sectional online survey in May 2021 for seven days with adult Canadian federally-authorized medical cannabis patients (N = 2697) registered with two global cannabis companies to evaluate patient perceptions of Primary Care Provider (PCP) knowledge of medical cannabis and communication regarding medical cannabis with PCPs, including PCP authorization of licensure and substitution of cannabis for other medications.

Results: Most participants (62.7%, n = 1390) obtained medical cannabis authorization from their PCP. Of those who spoke with their PCP about medical cannabis (82.2%, n = 2217), 38.6% (n = 857) reported that their PCP had “very good” or “excellent” knowledge of medical cannabis and, on average, were moderately confident in their PCP’s ability to integrate medical cannabis into treatment. Participants generally reported higher ratings for secondary care providers, with 82.8% (n = 808) of participants rating their secondary care provider’s knowledge about medical cannabis as “very good” or “excellent.” Overall, 47.1% (n = 1269) of participants reported substituting cannabis for pharmaceuticals or other substances (e.g., alcohol, tobacco/nicotine). Of these, 31.3% (n = 397) reported a delay in informing their PCP of up to 6 months or more, and 34.8% (n = 441) reported that their PCP was still not aware of their substitution. Older, female participants had higher odds of disclosing cannabis substitution to their PCPs.

Conclusion: Most of the surveyed Canadian medical cannabis patients considered their PCPs knowledgeable about cannabis and were confident in their PCPs’ ability to integrate cannabis into treatment plans. However, many surveyed patients substituted cannabis for other medications without consulting their PCPs. These results suggest a lack of integration between mainstream healthcare and medical cannabis that may be improved through physician education and clinical experience.


Kruger, J.S., & Kruger, D.J. (2022). Delta-8-THC: Delta-9-THC’s nicer younger sibling? Journal of Cannabis Research, 4, 4.

Background: Products containing delta-8-THC became widely available in most of the USA following the 2018 Farm Bill and by late 2020 were core products of hemp processing companies, especially where delta-9-THC use remained illegal or required medical authorization. Research on experiences with delta-8-THC is scarce, some state governments have prohibited it because of this lack of knowledge.

Objective: We conducted an exploratory study addressing a broad range of issues regarding delta-8-THC to inform policy discussions and provide directions for future systematic research.

Methods: We developed an online survey for delta-8-THC consumers, including qualities of delta-8-THC experiences, comparisons with delta-9-THC, and open-ended feedback. The survey included quantitative and qualitative aspects to provide a rich description and content for future hypothesis testing. Invitations to participate were distributed by a manufacturer of delta-8-THC products via social media accounts, email contact list, and the Delta8 Reddit.com discussion board. Participants (N = 521) mostly identified as White/European American (90%) and male (57%). Pairwise t tests compared delta-8-THC effect rating items; one-sample t tests examined responses to delta-9-THC comparison items.

Results: Most delta-8-THC users experienced a lot or a great deal of relaxation (71%); euphoria (68%) and pain relief (55%); a moderate amount or a lot of cognitive distortions such as difficulty concentrating (81%), difficulties with short-term memory (80%), and alerted sense of time (74%); and did not experience anxiety (74%) or paranoia (83%). Participants generally compared delta-8-THC favorably with both delta-9-THC and pharmaceutical drugs, with most participants reporting substitution for delta-9-THC (57%) and pharmaceutical drugs (59%). Participant concerns regarding delta-8-THC were generally focused on continued legal access.

Conclusions: Delta-8-THC may provide much of the experiential benefits of delta-9-THC with lesser adverse effects. Future systematic research is needed to confirm participant reports, although these studies are hindered by the legal statuses of both delta-8-THC and delta-9-THC. Cross-sector collaborations among academics, government officials, and representatives from the cannabis industry may accelerate the generation of knowledge regarding delta-8-THC and other cannabinoids. A strength of this study is that it is the first large survey of delta-8 users, limitations include self-report data from a self-selected convenience sample.


Kruger, D.J. & Kruger, J.S. (2021). Consumer experiences with delta-8-THC: Medical use, pharmaceutical substitution, and comparisons with delta-9-THC. Cannabis and Cannabinoid Research.

Introduction: Cannabis products containing delta-8-THC became widely available in most of the United States in late 2020 and rapidly became a significant source of revenue for hemp processing companies, especially in states where use of delta-9-THC remains illegal or requires professional authorization for medical use. Scientific research on the use of delta-8-THC is scarce, previous clinical studies included a combined total of 14 participants, leading some state governments to prohibit it until its properties and effects are better understood.

Methods: Researchers developed an online survey for delta-8-THC consumers addressing a broad range of issues regarding delta-8-THC, including use for the treatment of health and medical conditions. Previous survey studies on the medical use of cannabis and cannabis products informed survey components.

Results: Patterns of delta-8-THC use had both similarities with and differences from the use of delta-9-THC cannabis and products. Administration methods were primarily edibles (64%) and vaping concentrates (48%). About half of the participants (51%) used delta-8-THC to treat a range of health and medical conditions, primarily anxiety or panic attacks (69%), stress (52%), depression or bipolar disorder (46%), and chronic pain (41%). Participants compared delta-8-THC very favorably with both delta-9-THC and pharmaceutical drugs and reported substantial levels of substitution for both. Most participants did not inform their primary care provider of their delta-8-THC use (78%) and were not confident of their primary care provider's ability to integrate medical cannabis into their treatment (70%). Knowledge of effective dosages was low, and participants' knowledge of delta-8-THC was primarily from the Internet and their own experiences.

Conclusion: Harm reduction is a central component of public health. Although the legal environment is becoming more restrictive for delta-8-THC in comparison to delta-9-THC, results suggest that delta-8-THC may be equally effective for desired purposes of cannabis use and lower in undesirable or adverse effects. All policies and practices should be informed by empirical evidence. Considerable research will be needed to systematically verify the patterns reported by participants, and collaborations among academic researchers, government, and the cannabis industry may be valuable in developing the knowledge base for delta-8-THC and other cannabinoids.


Kruger, D.J., Mokbel, M.M., Clauw, D.J., & Boehnke, K.F. (2021). Assessing healthcare providers’ knowledge of medical Cannabis. Cannabis and Cannabinoid Research.

Introduction: Many health care providers would benefit from greater knowledge and awareness of medical cannabis, even if they choose not to integrate it into their medical practice. Unfortunately, health care providers generally report low knowledge of medical cannabis and cite this lack of knowledge as a barrier to making patient recommendations. It is important to understand health care providers' medical cannabis knowledge and its correlates. However, few studies have rigorously assessed clinically relevant cannabis-related knowledge, instead typically focusing on attitudes toward cannabis and perceived knowledge.

Methods: Physicians in a university-affiliated health system completed an anonymous online survey. The survey assessed participants' basic demographics and medical experience, experiences with cannabis education, beliefs about their knowledge of and competency regarding medical cannabis, and knowledge of medical cannabis in relation to the current scientific evidence.

Results: The average level of medical cannabis knowledge was 58% correct, with scores ranging from 39% to 78% correct. Perceived cannabis knowledge predicted actual knowledge, and those who pursued self-initiated study or attended a lecture on medical cannabis had higher knowledge levels.

Conclusion: Levels of factual knowledge about medical cannabis among physicians were moderate. Our results highlight the mismatch between physician knowledge and cannabis policy. We offer our brief, 10-min assessment as a baseline for characterizing cannabis knowledge, acknowledging that the content and interpretation may change as knowledge advances.


Kruger, J.S., Kruger, D.J., & Collins, R. L. (2021). Knowledge and practice of harm reduction strategies among people who report frequent cannabis use. Health Promotion Practice, 22, 24-30.

We examined knowledge and practice of harm reduction strategies among people who use cannabis attending an annual public cannabis advocacy event. We also assessed the sources from which they glean information about cannabis. Participants (N = 472) completed a brief survey assessing cannabis use, sources for information on cannabis, and harm reduction strategies. Participants’ knowledge of cannabis was based mostly on their own experiments and experiences rather than on information from health professionals. Participants generally had low accuracy in identifying effective harm reduction techniques and low rates of utilizing effective harm reduction techniques, using them at the same rate overall as techniques without empirical support. Results from this survey will be useful to public health professionals developing and implementing harm reduction educational strategies related to cannabis use.


Kruger, D.J., Korach, N.J., & Kruger, J.S. (2021). Requirements for cannabis product labeling by US state. Cannabis and Cannabinoid Research, 7, 156-160.

Introduction: As more states allow for medical and nonregistered adult cannabis (i.e., marijuana) use, ensuring proper utilization should be a priority. Standardized labeling for foods and pharmaceutical drugs promotes consumer safety. This study investigated cannabis product labeling requirements in the United States.

Materials and Methods: Researchers compiled the requirements for cannabis product labeling across 31 U.S. states with medical cannabis programs from state regulatory publications.

Results: Information requirements ranged considerably by U.S. state. All states required delta-9-tetrahydrocannabinol content and manufacturer contact information, >80% of states required the batch number, health risks, production tracking, a cannabis symbol, cannabidiol content, children disclaimer, and an impairment disclaimer. There appeared to be a random pattern in requirements for other specific items. The relationships between the extent of cannabis product labeling requirements and the number of years that a state had a medical cannabis program or whether states allowed nonregistered adult use cannabis were not significant, although there was a trend for nonregistered adult use states to require more recommended label attributes.

Conclusion: A comprehensive framework for cannabis use is needed to protect the public, maximize benefits, and minimize harms and risks. Standardization of cannabis product labeling requirements would benefit consumers and promote safer and more effective usage of cannabis products.


Boehnke, K.F., Litinas, E., Worthing, B., Conine, L., & Kruger, D. (2021). Communication between healthcare providers and medical cannabis patients regarding referral and medication substitution. Journal of Cannabis Research, 3, 2.

Background People report using cannabis as a substitute for prescription medications but may be doing so without the knowledge of their primary health care providers (PCPs). This lack of integration creates serious concerns, e.g., using cannabis to treat medical conditions that have established treatment options.

Methods We conducted an anonymous, cross-sectional online survey among patrons of a medical cannabis dispensary in Michigan (n = 275) to examine aspects of their relationship with their PCP and their perceptions of PCP knowledge related to cannabis.

Results Overall, 64% of participants initiated medical cannabis use based on their own experiences vs. 24% citing advice from their PCP. Although 80% reported that their PCP knew they currently used medical cannabis, 41% reported that their PCP had not always known. Only 14% obtained their medical cannabis authorization from their PCP. Only 18% of participants rated their PCP’s knowledge about medical cannabis as very good or excellent and only 21% were very or completely confident in their PCP’s ability to integrate medical cannabis into their treatment. Although 86% had substituted cannabis for pharmaceutical medications, 69% (n = 134) of those who substituted reported some gap in their PCP’s knowledge of their substitution, and 44% (n = 86) reported that their PCP was currently unaware of their substitution.

Conclusions Patients frequently substitute cannabis for prescription drugs, often without PCP knowledge. Although most participants disclosed cannabis use to their PCP, their perceptions of PCP knowledge ranged widely and many obtained medical cannabis licensure from an outside physician. Our results highlight the need for standardized physician education around appropriate medical cannabis use.


Kruger, D.J., Kruger, J. S., Bednarczyk, E.M., & Prescott, W. A. (2021). Cannabis education in United States pharmacy colleges and schools. Journal of the American College of Clinical Pharmacy, 4, 616-621.

Introduction Given the rapid change in legal status and rise in cannabis use within the United States (U.S.), pharmacists will increasingly require competence in issues related to cannabis, especially for medical use. Pharmacy students and professionals in other health fields report low levels of cannabis knowledge, and medical cannabis users report that their knowledge is mostly from their own experiences and the internet. Several pharmacy organizations have advocated for pharmacists' education on therapeutic and legal issues related to medical cannabis.

Objectives To determine the extent to which cannabis and its medical use are covered in the educational curricula of U.S. schools and colleges of pharmacy, plans for future coverage of medical cannabis, and differences by the state-level legal status of cannabis.

Methods Pharmacy schools and colleges located within the U.S. were identified via the Accreditation Council for Pharmacy Education website. A 19-item survey was developed by researchers with experience in curriculum development and pharmaceutical issues related to cannabis. One individual from each school provided detailed information on the inclusion of medical cannabis/marijuana topics in their Doctor of Pharmacy program.

Results Two-thirds (67%) of programs responded to the survey. Most programs (85.4%) had content on medical cannabis available in their curriculum, 53.1% in their required curriculum, 65.6% in their elective curriculum, and 33.0% in both their required and elective curricula. A small proportion (16.7%) had a stand-alone medical cannabis elective course. Stand-alone electives had the most comprehensive coverage of cannabis topics. General required and elective courses had minor differences in comprehensiveness.

Conclusion Results demonstrate a moderately rapid expansion in cannabis coverage in pharmacy curricula, although coverage of cannabis topics is rarely comprehensive. Additional efforts are needed to integrate cannabis into coursework and experiential learning experiences.


Boehnke, K.F., McAfee, J., Ackerman, J., & Kruger, D.J. (2021). Medication and substance use increase among people using cannabis medically during the COVID-19 pandemic. International Journal of Drug Policy, 92, 103053.

Background The ongoing COVID-19 pandemic strains the medical system, limiting access to healthcare services. Many people use cannabis medically for chronic health conditions and as a substitute for other medications. As such, changes in cannabis access associated with COVID-19 may result in increased non-cannabis drug use.

Methods We recruited N = 353 individuals through Amazon Mechanical Turk who reported current medical cannabis use in April and May of 2020. We assessed the effects of the COVID-19 pandemic on patterns of medication and substance use, as well as on cannabis use patterns.

Results Over half of participants either started using or increased use of medications or substances because of the COVID-19 pandemic, most commonly alcohol and sleep aids. Over a third of participants increased cannabis use while 25% decreased cannabis use. Approximately 40% of participants who increased or started use of medications/substances (other than cannabis) reported doing so because of changed access to medical cannabis.

Conclusion The reported increase in drug use among people using medical cannabis is concerning. Because the pandemic will likely continue for months (or even years), having a better understanding of why this is occurring is critical for developing effective harm-reduction strategies in this population.


Kruger, D.J., Moffet, I.M., Seluk, L.C., & Zammit, L.A. (2020). A content analysis of Internet information sources on medical cannabis. Journal of Cannabis Research, 3, 29.

Background Medical cannabis users report that their knowledge regarding cannabis is predominantly from their own personal experiences and the Internet.

Objective We summarize and describe information found through Internet searches on medical cannabis in English language websites.

Methods We used terms related to medical cannabis in the Google search engine between November and December 2019. Resulting websites were catalogued and coded for content, including mentions of health and medical conditions, pharmacology, dosage, harmful or adverse effects, harm reduction techniques, cautions or warnings, products for sale, and credentials.

Results We coded 344 web pages on 179 unique websites. Cannabis was mentioned for the treatment of 151 different medical and health conditions, only four of the twenty most frequently mentioned conditions have received substantial empirical support for cannabis or cannabinoid treatment. Information content varied widely across sites, only a small proportion of sites included information on pharmacology, dosage, risks, and other aspects that are requirements for pharmaceutical drugs. Information provided was only moderately related to conclusions in the emerging scientific literature.

Conclusions Given the rise in cannabis use within the U.S. and the reliance on the Internet as a source of information, considerable efforts are needed to provide accurate on-line cannabis education to minimize harms and maximize benefits for individuals and society.


Kruger, D.J., Kruger, J.S., & Collins, R. L. (2020). Frequent cannabis users demonstrate low knowledge of cannabinoid content and dosages. Drugs: Education, Prevention & Policy, 28, 97-103.

Background: The legal status of cannabis is rapidly evolving, outpacing systematic research and educational efforts.

Aims: We investigated knowledge of cannabinoid content and dosages among frequent cannabis users.

Methods: A brief survey was administered in April 2019 (N = 472) at a cannabis advocacy event in a state with legal medical and recreational adult cannabis use.

Findings: Most participants (67%) used cannabis every day, 85% used cannabis for health or medical purposes. Knowledge of cannabis was mostly from participants’ own experiences (78%), with some receiving information from a medical cannabis caregiver or dispensary (23%) or their primary care provider (18%). The majority reported not knowing the effective dosages of THC (53% of participants) or CBD (68% of participants), other participants gave average estimates of 91 mg and 177 mg, respectively. Participants’ average estimates for high-THC (52%) and high-CBD (53%) as well as low-THC (28%), and low-CBD (30%) strains of cannabis were considerably higher than currently accepted definitions. Men, European Americans, and participants who had medical cannabis cards were more accurate in cannabinoid concentration estimates.

Conclusions: Frequent cannabis users reported low knowledge of and substantially overestimated cannabinoid content. The importance of education and research on cannabinoid dosages grows with increasing cannabis accessibility.


Kruger, D.J., Kruger, J.S., & Collins, R. L. (2020). Cannabis enthusiasts’ knowledge of medical treatment effectiveness and increased risks from cannabis use. American Journal of Health Promotion, 34, 436-439.

Purpose: To compare cannabis enthusiasts’ knowledge about cannabis risks and effectiveness in treating medical conditions with existing empirical evidence.

Design: A brief survey assessed cannabis use, information sources, and knowledge about risks and effectiveness.

Setting: A cannabis advocacy event in April 2019 in a state with legal medical and recreational cannabis.

Participants: Demographically diverse adults (N = 472) who frequently used cannabis; 85% used cannabis for health or medical purposes.

Measures: Participants reported the sources of their cannabis information, health conditions they thought cannabis was effective in treating (n = 10), and health risks increased by cannabis (n = 6). Conditions and risks were based on ratings of evidence (ie, from substantial to insufficient) for therapeutic effects and risks identified in a review by The National Academies of Sciences, Engineering, and Medicine (NASEM, 2017).

Analyses: Chi-square tests examined the correspondence between participants’ knowledge and NASEM conclusions.

Results: Most participants’ (95% confidence interval [CI]: 74%-81%) knowledge of cannabis was from their own experiences; 18% (95% CI: 14%-21%) received information from primary care providers. On average, participants’ beliefs matched NASEM conclusions for half of effectiveness (95% CI: 50%-53%) and risk items (95% CI: 55%-57%). Many (95% CI: 38%-42%) thought that cannabis use did not increase any risk. Contrary to NASEM conclusions, many thought cannabis was effective in treating cancer (76%), depressive symptoms (72%), and epilepsy (68%). Those who received cannabis information from their primary care providers had better knowledge of medical effectiveness. Medicinal cannabis use frequency inversely predicted knowledge of medical effectiveness and increased risks of adverse events.

Conclusion: There were considerable discrepancies between cannabis users’ knowledge and available evidence, highlighting the need for more research and education (by physicians, caregivers, and dispensaries) on effectiveness and health risks, especially for users with specific health issues such as pregnant women and people with depression.


Kruger, J.S., Blavos, A., Castor, T.S., Wotring, A., Wagner-Greene, V.R., & Glassman, T.J., & Kruger, D.J. (2019). Manipulation checking the munchies: Validating self-reported dietary behaviors during cannabis intoxication. Human Ethology, 34, 10-16.

The prevalence and rate of cannabis use will likely increase as the relevant legal framework becomes more permissive across many municipalities. All policies and practices should be informed by scientific evidence and the public health framework for cannabis users may benefit from research and interventions promoting harm reduction. Naturalistic observations are particularly valuable for understanding patterns of human behavior and can complement and validate information collected through other methods, such as self-report surveys. Observational research may be especially valuable for addressing potentially controversial topics where behaviors are socially stigmatized and/or illegal. The current study examined the relationship between self-reported dietary behaviors and food incentive choices among individuals intoxicated with cannabis. Participants at a cannabis decriminalization advocacy event completed brief surveys on cannabis use and dietary habits. Survey administrators offered an incentive choice of a food items; fruit and chips/crisps. Researchers documented choices of food incentives and three trained coders categorized self-reported dietary habits. Participants (N = 275) reported eating unhealthy food (77%), eating healthy food (23%), and avoiding consuming food when intoxicated (7%). Participants also reported eating more food when intoxicated with cannabis and being more likely to eat unhealthy food when intoxicated compared to at other times. Food incentive choices predicted self-reported habits for both consuming healthy and unhealthy foods. Observational results validated self-reported dietary habits and confirmed common stereotypes.


Kruger, D.J., & Kruger, J.S. (2019). Medical cannabis users’ comparisons between medical cannabis and mainstream medicine. Journal of Psychoactive Drugs, 51, 31-36.

An evidence-based approach is needed to shape policies and practices regarding medical cannabis, thereby reducing harm and maximizing benefits to individuals and society. This project assesses attitudes towards and utilization of medical cannabis and the mainstream healthcare system among medical cannabis users. The research team administered brief hard copy surveys to 450 adults attending an annual public event advocating for cannabis law reform. Among usable responses (N = 392), the majority (78%) reported using cannabis to help treat a medical or health condition. Medical cannabis users reported a greater degree of use of medical cannabis and a greater degree of trust in medical cannabis compared to mainstream healthcare. In comparison to pharmaceutical drugs, medical cannabis users rated cannabis better on effectiveness, side effects, safety, addictiveness, availability, and cost. Due to the medical use of cannabis, 42% stopped taking a pharmaceutical drug and 38% used less of a pharmaceutical drug. A substantial proportion (30%) reported that their mainstream healthcare provider did not know that they used medical cannabis. Other issues identified included lack of access to mainstream healthcare, self-initiated treatment of health issues, little knowledge of psychoactive content, and heavy cannabis use.


Kruger, D.J., Kruger, J.S., Wagner-Greene, V.R., Wotring, A., Castor, T.S., Blavos, A., & Glassman, T.J. (2019). Health related behaviors, health outcomes, and health access issues among cannabis users in the Midwestern USA. Journal of Alcohol and Drug Education, 63, 8-25.

This study identifies new areas for risk-reduction strategies and research with regular cannabis users. Participants at a cannabis advocacy event in the Midwestern USA completed a survey including items from the Behavioral Risk Factor Surveillance System. Most participants (70%) reported using cannabis to treat a medical condition, though a smaller portion (28%) had a med- ical marijuana card. Participants reported several health risks associated with cannabis use, including driving a vehicle while high on cannabis, using cannabis laced with some other drug and having more intense experiences than they intended. Nearly one-quarter of participants indicated they did not have any health care coverage and; consequently, not being able to see a doctor when they needed to because of the cost. The findings indicate a variety of health issues in cannabis users that warrant atten- tion from health educators and researchers. Additional research is needed to evaluate the effectiveness of health-promoting inter- ventions in this population