Weed my lips: The good and not-so-good aspects of cannabis use among patients, part 2

Our patients have never had such widespread access to cannabis, a drug we know very little about and whose major routes of administration all involve the oral cavity. In "Weed my lips" part 1, we explored the not-so-good aspects of its use among our patients, which, for the most part, have to do with misconceptions about cannabis’s systemic effects. Here, we’ll explore some of the good aspects of its use, which, interestingly, are supported by scientific research.

Cannabis sativa is one of the world's oldest cultivated plants. The earliest written records of the human use of cannabis date from the 6th century BC. Many 19th-century practitioners ascribed medicinal properties to cannabis after the drug found its way to Europe. In 1851, cannabis was included in the third edition of the Pharmacopoeia of the United States (USP). Subsequent revisions of the USP described in detail how to prepare extracts and tinctures of dried cannabis flowers to be used as analgesic, hypnotic, and anticonvulsant. However, growing concerns about cannabis resulted in its being outlawed in several states in the early 1900s and federally prohibited in 1937 with the passage of the Marihuana Tax Act. In response to these concerns, in 1942 the American Medical Association removed cannabis from the 12th edition of US Pharmacopeia.

The US Food and Drug Administration (FDA) has licensed three drugs based on cannabinoids. Dronabinol, the generic name for synthetic Δ9-THC, is marketed under the trade name of Marinol and is clinically indicated to counteract the nausea and vomiting associated with chemotherapy and to stimulate appetite in patients with AIDS who are affected by wasting syndrome. A synthetic analog of Δ9-THC, nabilone (Cesamet), is prescribed for similar indications. In July 2016, the FDA approved Syndros, a liquid formulation of dronabinol, for the treatment of patients experiencing chemotherapy-induced nausea and vomiting who have not responded to conventional antiemetic therapies. Epidiolex, a concentrated CBD oil (>98% CBD), was developed by GW Pharmaceuticals as an antiseizure medication for Dravet and Lennox-Gastaut syndromes.

Expert opinions on the therapeutic effects of cannabis

In March 2016, the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine (the National Academies) was asked to convene a committee of experts to conduct a comprehensive review of literature regarding the health consequences of using cannabis or its constituents that had appeared since the publication of the 1999 Institute of Medicine (IOM) report Marijuana and Medicine. In January 2017, the National Academies of Sciences published its landmark report entitled “The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research.”

Part II of this report, “Therapeutic Effects of Cannabis and Cannabinoids,” discusses the health effects of cannabis and cannabinoids used for therapeutic purposes in relation to the most commonly reported conditions for medical cannabis use (in states where usage is legal), as well as the current qualifying ailments recognized by state medical marijuana programs. Most of the evidence reviewed in this chapter derives from clinical and basic science research conducted for the specific purpose of answering the question of whether cannabis and/or cannabinoids are an effective treatment for a specific disease or health condition.

The results reached by the committee include the following:¹

• In adults with chemotherapy-induced nausea and vomiting, oral cannabinoids are effective antiemetics.
• In adults with chronic pain, patients who are treated with cannabis or cannabinoids are more likely to experience a clinically significant reduction in pain symptoms.
• In adults with multiple sclerosis-related spasticity, short-term use of oral cannabinoids improves patient-reported spasticity symptoms.

In addition, the committee concluded that:

• There is moderate evidence that cannabis or cannabinoids are effective for improving short-term sleep outcomes in individuals with sleep disturbance associated with obstructive sleep apnea syndrome, fibromyalgia, chronic pain, and multiple sclerosis.

There is limited evidence that cannabis or cannabinoids are effective for:

• Increasing appetite and decreasing weight loss associated with HIV/AIDS
• Improving clinician-measured multiple sclerosis spasticity symptoms
• Improving symptoms of Tourette syndrome
• Improving anxiety symptoms, as assessed by a public speaking test, in individuals with social anxiety disorders
• Improving symptoms of posttraumatic stress disorder (PTSD)

What it means for hygienists

The debate over the efficacy of cannabinoids in treating disease may well rage on until legalization at the federal level allows for advanced research and clinical trials. However, we, as dental professionals, can only be encouraged that, even with the limited evidence we have now, cannabinoids may be effective in treating conditions for which the other medications we currently use are not always very effective. For dental hygienists, this brings the promise that cannabinoids may indeed be worthwhile adjuncts in disease state management for their patients.

Editor's note: This article appeared in the January 2022 print edition of RDH.

Reference

1. National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Board on Population Health and Public Health Practice; Committee on the Health Effects of Marijuana: An Evidence Review and Research Agenda. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington (DC): National Academies Press (US). January 12, 2017. 4, Therapeutic Effects of Cannabis and Cannabinoids. https://www.ncbi.nlm.nih.gov/books/NBK425767/