Tip Sheets

Tips for reporting about cannabis fever and the aging boomer

By Liz Scherer

As of March 2021, 36 states, the District of Columbia, and three U.S. territories (Guam, Puerto Rico, and U.S. Virgin Islands) have legalized medical cannabis, with 15 states permitting both medical and adult recreational cannabis use. Three additional states — Virginia, South Dakota, and New York — have passed recent legislation expanding use into the recreational/retail space.

Cannabis fever undoubtedly has taken hold across the nation and there’s one group in particular who appear eager participants: older adults. Data presented during the American Association for Geriatric Psychiatry’s Annual meeting demonstrates a 14% increase over three years in the proportion of older (mean age 72.3 years) Canadian adults reporting medical cannabis use. Notably, most (60%) were women, echoing previously-reported usage trends among women and gender-related drivers.

This growing phenomenon among older adults is not without risk. Not only are older adults likelier than younger peers to experience adverse drug reactions, but the small number of randomized clinical trials and comprehensive medical education around cannabinoid therapeutics has left clinicians largely unprepared to prescribe, let alone educate their older patients effectively.

Cannabis remains a Schedule 1 controlled substance, placing at odds the federal and state governments. Unfortunately, this status has unintentionally targets the older adult user, restricting research that focuses on aging-related pharmacokinetic and pharmacodynamic changes that affect cannabis administration and dosing. Moreover, skilled nursing facilities (which receive Medicare and Medicaid funding and must comply with federal laws) cannot purchase, store, and use medicinal cannabis as a therapeutic strategy for its residents.

Cannabis and symptom management

Although medical cannabis has been found in historical records as far back as 2700 BC and in the U.S. Pharmacopeia starting in1850, research into the endocannabinoid system during the 1990s placed cannabinoid therapeutics back into the spotlight. It helped set the stage for today’s burgeoning user base.

As a therapeutic agent, cannabis is considered especially useful for treating conditions that lack effective conventional options or where treatment side effects outweigh the benefits, according to a 2018 review in the European Journal of Internal Medicine. These include chronic pain syndromes, central sensitivity syndromes (e.g., fibromyalgia, migraines, irritable bowel syndrome) and multiple sclerosis, intractable epileptic seizures and refractory nausea.

Data suggest that older adults tend to use cannabis to treat chronic medical conditions such as cancer, HIV/AIDs, and glaucoma. A study outlining patterns of use among older New York State patients also underscores that substantial numbers specifically seek therapeutic support for severe or chronic pain.

Yet, the lack of robust randomized controlled studies has created a challenge for the medical community, which largely is unprepared to address patient questions and concerns and lacks evidence-based guidelines to drive dosing strategies in a challenging patient population. Recent survey data suggest that roughly 90% of medical school residents did not feel prepared to prescribe medicinal cannabis. Only a quarter believed that they were educated enough to answer questions.

However, with last year’s release of Samoon Ahmad’s and Kevin Hill’s Medical Marijuana: a Clinical Handbook, clinicians have an opportunity to fill some of these knowledge gaps.

Into the Weeds: Practical Considerations

The endocannabinoid system is ubiquitous throughout the human body and across species. Compounds interacting with this system are either produced within the body itself (endocannabinoids) or by the cannabis plant (phytocannabinoids). However, as Samoon Ahmad points out in the prologue to his textbook, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are simply the tip of the iceberg; “focusing solely on the concentrations of these two phytocannabinoids in an attempt to predict user experience produces an incomplete picture,” he writes.

Indeed, many chemovars contain various cannabinoids and other components (such as terpenoids) that produce a wide range of pharmacological and therapeutic effects. Among the many factors that determine onset and duration of action, absorption is one of the most important and can be influenced by stomach contents/recent meals, how deeply one inhales and holds their breath (if inhalation is the preferred method), as well as by temperature. Cannabinoid lipophilicity mainly affects bioavailability and absorption when oral or topical delivery is preferred.

Many older adults report a preference for sublingual tincture administration, while others prefer edibles over smoking or other forms of inhalation. Oral administration is advantageous for treating chronic disease symptoms, but delayed onset presents titration challenges, a significant disadvantage among older adults. Fortunately, older medical cannabis patients often prefer CBD-dominant chemovars formulated with small amounts of THC, which benefit from fewer adverse events and reduce the risk for falls, dizziness, or cognitive effects. Conversely, CBD affects several biological targets important to drug metabolism (e.g., CYP3A4/2C19) and excretion (e.g., P-glycoprotein)

Although the overall safety profile of cannabis is still being elucidated, it is relatively safe compared with many other medications. Still, drug-drug interactions are a critical consideration, especially in older patients. Aside from the dearth of drug interaction studies, many issues have been reported in cases where cannabis is used concurrently with central nervous system depressants.

When approaching the older patient interested in trying medicinal cannabis, a general rule of thumb in dosing is to “start low and go slow” to mitigate THC-specific side effects (which are dose-dependent and rate-limiting). Close monitoring is recommended, especially in the early stages of use when the most optimal dosing and titration strategy is being explored.

Follow-up also is recommended to keep track of efficacy, adverse events, need for dose adjustment and/or formulation changes, and assess concomitant medication changes.

Medicinal cannabis is quickly becoming part of the therapeutic landscape. In his textbook, Co-author Kevin Hill notes that “patients will continue to turn to medical cannabis; we want to educate health care professionals so that they are in a better position to help patients when this happens.”


Because cannabinoid therapeutics is such a complex topic, expert sources tend to be highly specialized. Below are several who can speak to both the science and its broader clinical applications.

  • Ethan Russo M.D., CEO of CReDO Science, is a board-certified neurologist and the author/co-author of over 50 peer-reviewed journal articles and seven books on medical cannabis and the endocannabinoid system. A veteran of GW Pharmaceuticals, Russo served as the medical monitor and study physician for the clinical trials of Sativex® and Epidiolex®, the first cannabis-based pharmaceuticals to market.

  • Vincenzo di Marzo Ph.D., Canada Excellence Research chair on the Microbiome — Endocannabinoidome Axis in Metabolic Health, Université Laval, Quebec, Canada, is internationally recognized as an authority on endocannabinoid pharmacology. He also heads a research group currently studying intestinal microbiota and their impact on obesity-related inflammation, Type-2 diabetes, and cardiometabolic disease.

  • Caroline MacCallum M.D., clinical Instructor of medicine, University of British Columbia, Vancouver Coastal Health Research Institute, Changepain, is a specialist in internal medicine with expertise in complex pain and cannabinoid medicine. MacCallum is the medical director of Greenleaf Medical Clinic, where she has assessed and developed cannabinoid treatment plans for more than 5,000 patients and an expert in cannabis dosing, safety, and polypharmacy reduction and substitution.

Additional sources


Ahmad S, Hill KP. Medical Marijuana: A Clinical Handbook. Walters Kluwer: 2020.

Kaufmann CN, Kim A, Miyoshi M, Han BH. Patterns of medical cannabis use among old adults from a cannabis dispensary in New York State. Cannabis Cannabinoid Res. 2020

Levy C Galenbeck E, Magid K. Cannabis for symptom management in older adults. Med Clin N Am. 2020.

MacCallum CA, Russon EB. Practical considerations in medical cannabis administration and dosing. Eur J Med. 2018

Manning L, Bouchard L. Medical cannabis use: exploring the perceptions and experiences of older adults with chronic conditions. Clin Gerontol. 2021.

Minerbi A, Hȁuser W, Fitzcharles MA. Medical cannabis for older patients. Drugs Aging. 2019.

Story ideas

  • What is the status of medical cannabis in your state and how are major health systems approaching burgeoning use among older patients?

  • How might different chemovars help treat older patients with chronic pain?

  • Despite federal laws, are they any strategies that nursing homes can use to assess and meet the interest in medical marijuana among their residents?

  • How have cannabis use and attitudes changed in the aging Boomer population?

  • What shifts are needed in medical schools to address the burgeoning use of medicinal cannabis?

Liz Scherer is an independent health journalist specializing in cannabinoid therapeutics, infectious diseases, and women’s health. She reports monthly on oncology breakthroughs for EveryDay Health and maintains a daily beat educating European clinicians on infectious and emerging infectious diseases.