Understanding Medical Cannabis

Critical Issues and Perspectives for Human Service Professionals

Joanne Levine, Joanne Levine

• Publisher: Routledge
• Year: 2020
• ISBN:
  9781000339444
• Edition: 1
• Topic: Medicine
• Subtopic: Medical Theory, Practice & Reference

This accessible text provides trainee human service providers and those currently working in the field with a comprehensive, cutting-edge overview of topics related to the medical and therapeutic use of cannabis.

Employing an interdisciplinary, biopsychosocial framework, the book explores the different biological, cultural, and policy contexts of medical cannabis from a wide range of perspectives including practitioners, academics, and medical cannabis advocates. This book bridges the gap between theory and practice and underscores the urgent need for expanded and rigorous scientific research as medical cannabis is increasingly legalized, that may result in new cannabis-based medicines and help in identifying what health risks cannabis use may present.

Chapters are both evidence-based and practical, weaving in learning objectives, review questions, and varied case examples, all of which will prepare students and professionals for the reality of working with medical cannabis consumers.

Part One

The Context of Cannabis: Culture, Clashes and Commerce

Chapter 1

Cannabis Ethnomedicine

Stephen Dahmer and Michael Balick

Introduction

Ethnobotany, the largest subdiscipline of ethnobiology, is generally defined as the “science of people’s interaction with plants” (Dunlap & Turner, 1995). Ethnomedicine refers to the study of traditional medical practices and is concerned with the cultural interpretation of health, diseases, and illness, as well as the healthcare-seeking process and traditional healing practices (Krippner, 2003). Cannabis sativa L. (cannabis) (Figure 1.1) has a long history of traditional use as a medicine by many cultures around the world, dating back 6,000 years (Small, 2015). In addition to medicinal use, this versatile plant was recognized long ago as a source of food and fiber. This long-shared history with humans has been rife with debate claiming the plant and its flowers both pariah and panacea, both scourge and benefactor, both hoax and soothing medicine (Hudson & Puvanenthirarajah, 2018; Abel, 1980; www.nationalacademies.org, 2017).

Figure 1.1 Thomé, O.W., Flora von Deutschland Österreich und der Schweiz, Tafeln, vol. 2: t. 182 (1885) Source: plantillustrations.org

Cannabis is an herbaceous annual plant with ancient origins mainly in Western or Central Asia (Russo et al., 2008, Small, 2015) and is arguably one of the most multipurpose ethnobotanical resources as fiber (stalks), food (seeds), medicine (flowers), and recreational/religious purposes (Piluzza et al., 2013). Its versatility ranges from the manufacturing of fish nets, ropes, textiles, paper, bricks, parachutes, and American flags (Onaivi, 2002) to being touted as useful for 25,000 products “ranging from dynamite to Cellophane” (Small & Marcus, 2002). It has been referred to as the oldest known cultivated fiber plant (Schultes et al., 2001), with some suggesting that its use goes back 8,500 years ago in China (Cherney & Small 2016).

The discovery of where cannabis affects the human biological system—the endocannabinoid system (ECS)—combined with a recent surge in acceptance and legitimacy of this plant, has led to an explosion of research regarding potential medical applications of cannabis and the cannabinoid components that it produces (Treister-Goltzman et al., 2019). However, despite this recent popularity, the plant has been a part of healing traditions in many cultures throughout time and across the globe, ever-present in periods of favor and absolute disdain.

Although cannabis has often been framed as a “scapegoat” for drug abuse and xenophobia (Steen, 2010), it provides a contemporary mirror for modern medicine, rooted in an extensive history that reflects on the definition of the term “medicine.” Cannabis may also offer a renewed possible argument and path for the use of whole plant botanicals in the western medicine paradigm. Understanding the history of human use of cannabis as medicine may not only help prioritize research on potential therapeutic applications, challenging the single molecule pharmaceutical approach, but also potentially help avoid pitfalls in our relationship with a psychoactive plant that has potential for abuse.

This chapter will take the reader through the topsy-turvy history of the cannabis plant as medicine, including both historical and contemporary medicinal uses of cannabis in various cultural contexts and medical systems. Clarke and Merlin (2016), Mechoulam (1986), and Russo (2007) offer additional, comprehensive resources that consider cannabis’s evolution and widespread, diverse use by humans, and readers can find information on cannabis and its use in treating specific conditions in Chapters 3 and 4.

Plants as Medicine

Plants play an essential role in contemporary medicine, both at the primary care level and for specialized therapies. Today about 80% of the world’s population rely heavily on plants and plant extracts for healthcare (Setzer et al., 2006). In addition, of the top 150 proprietary drugs used in the United States, 57% contain at least one major active compound currently or once derived from plants (Grifo & Rosenthal, 1997). The global market for herbal medicine has been valued at more than $60 billion U.S. dollars in annual sales (WHO, 2003). In the past, the traditional medicinal uses of plants have been a successful criterion used by the pharmaceutical industry in finding new therapeutic agents for the various fields of biomedicine (Cox, 1994), although this is less so today, where approaches depend more heavily on technology.

Cannabis was among the first plants cultivated by early people who adopted a more sedentary lifestyle, perhaps as much as 10,000 years ago (Russo et al., 2008). This led to selections of plants grown to obtain nutritious starch-containing food, tough water-resistant fibers, and euphoric and medicinal substances (Fort, 2012; Sauer, 1952). Cannabis continued to accompany the progress of the first human societies in the changes that occurred after the glacial Pleistocene epoch; sophisticated plaited basketry based on cannabis found at Czech Paleolithic sites is perhaps the world oldest archaeological evidence of cannabis use (Adovasio et al., 1996). Its use as an intoxicant likely solidified its use as a medicine and fostered its spread rapidly from Asia to the entire world.

Medicinal plants, despite serving as the foundation of traditional healing therapies for centuries, have not maintained a prominent visible status in the contemporary western medical paradigm. This institutionalized marginalization has also contributed to confusion and strong contradictory opinions about the value of plants, in particular cannabis and its use as a medicine. On one hand, it is argued that if cannabis were unknown, and bioprospectors were suddenly to find it in some remote mountain crevice, its discovery would no doubt be hailed as a medical breakthrough. Scientists would praise its potential for treating everything from pain to cancer and marvel at its rich pharmacopoeia because many of its chemicals mimic essential molecules in the human body (Craker, 2006). On the other hand, a gullible Googler could easily believe that we are on the brink of a miracle cure (Sides, 2015).

Cannabis: The Name

Marijuana, hashish, dope, bud, ganja, reefer, and whacky tabacky are among the many names given to cannabis throughout history. Few substances exhibit the wide variation of names afforded Cannabis sativa, reflecting our intimate and longstanding history with this plant and including more than 1,200 slang terms, with more than 2,300 names for individual chemovars or “strains.” “Cannabis” comes from the Latin word “cannabis” and the earlier Greek word κάνναβις (OED 2018) and is the scientific name given to the plant Cannabis sativa and its variants from which the drug is produced. It is argued that lawmakers adopted the foreign-sounding word “marijuana” precisely because they wanted to underscore that it was a Latino, particularly Mexican “vice” and thereby boost support among xenophobes for laws prohibiting the drug (National Hispanic Caucus, 2017).

The taxonomy of cannabis remains in debate by some taxonomists. Three arguments persist: supporting the idea that the genus Cannabis is made up of one (monotypic) highly variable species (Cannabis sativa L.); supporting the concept of two species; and supporting the concept of three species (polytypic) (Schultes et al., 1974; Small & Cronquist, 1976; Small, 2015) based upon morphological, geographical, ecotypic or chemotypic differences. The three hypothetical species include: Cannabis sativa Linnaeus, Cannabis indica Lamarck, and Cannabis ruderalis Janisch, each circumscribing several biotypes or subspecies (Clarke & Merlin, 2006; Small, 2015).

Most recently, Cannabis specialist Small (2015) suggested that there be considered a single but variable species, Cannabis sativa, divided into six groups based on their chemical composition, fiber and oil content, and evidence of hybridization. Schultes, et al. (1974) and Anderson (1980) suggested that there are three species differing fundamentally in terms of height and content of psychoactive molecules. This chapter refers only to cannabis to simplify the discussion, but it is imperative to note that naming for such a complex plant is especially important in deciphering medicinal value. A valuable delineation for medical purposes includes Δ-9-tetrahydrocannabinol (THC)-predominant (Type I cannabis), mixed THC: cannabidiol (CBD) (Type II), and CBD-predominant (Type III cannabis) (Lewis et al., 2018).

Cannabis: The Plant

Cannabis is a dioecious, rarely monoecious, autumn-flowering, short-day photoperiod, anemophilous (wind-pollinated) annual plant of the family Cannabinaceae, that can reach up to five meters in height (Clarke & Merlin, 2016; Farag & Kayser, 2017). It has been described as a sun-loving plant that thrives in open, nitrogen-rich environments, including rubbish piles created by humans (Small, 2015) and as a rapidly growing, highly adaptable, herbaceous species that spread widely around the world (Abel, 1980). Cannabis speciation occurred during the early Pleistocene epoch, and domestication occurred more than a few million years later in the same region (Clarke & Merlin, 2016). As a result of protracted coevolution and its relationship with humans, it has been postulated that cannabis has become a stronger, more adaptable, diversified, and widely-cultivated plant (McPartland & Guy, 2004).

Phytocannabinoids are predominantly, if not entirely, synthesized and sequestered in microscopic structures called trichomes (Mahlberg et al., 1984) (Figure 1.2). Most of the essential oils (monoterpenes and sesquiterpenes) found in cannabis are also located in these glandular structures (Malingré et al., 1975). When considering medical applications, it is important to recognize the importance of the female species, as physiologically active compounds are mostly present in the resin secreted from the trichomes of female plants.

Figure 1.2 Cannabis Glandular Trichomes—from the Greek τρίχωμα (trichōma) meaning “hair” Source: Photograph © Stephen Dahmer, MD

Cannabis grows vertically and produces new leaves mostly in pre-flowering phase, along with the production of new branches and nodes. During its growth, the plant requires a moderate level of environmental and soil humidity and a good light intensity. The form of the plant varies according to the climate and variety. In the wild, it most commonly grows as a persistent weed at the edge of the cultivated fields on soil with high nitrogen content (Brown, 1998).

Food as Medicine

When reviewing plants as medicine it is easy to focus on a purely pharmaceutical approach, e.g., as a drug treating a symptom or condition, and overlook the important role of plants as food and medicine. Since the beginning of human civilization, people have used plants as food and medicine, and the value of the two uses are sometimes combined into the concept of food-medicines (Vandebroek and Balick 2012). Both food and medicinal plants have interventional uses, especially in indigenous and local traditions. Food can be used as medicine and vice versa. This key ancient tradition in various areas of the world is especially pertinent today (Etkin & Ross 1982). Throughout history, many things were purely medicines, but medicines often became food if people learned to like them; many foods became merely medicines when people stopped relishing them; and all foods were considered to have medicinal value, positive or negative, with important effects on health (Anderson, 1988).

This concept of food as medicine applies to the traditional use of cannabis in other parts of the world as well. Historical claims of cannabis’s medicinal efficacy relate to absorption of phytocannabinoids (the physiologically active compounds found only in Cannabis sativa) into the bloodstream via swallowing as well as via inhalation. Chinese medical traditions, for example, hold that diet is the most important determinant of one’s health, and there are often no distinct boundaries between foods and medicine. Chinese physicians used the seeds of cannabis mainly for their vegetable oils and proteins. The seeds are rich in γ-linoleic acid (Anwar et al., 2006), and physicians recommended this topically for eczema and pso...

Table of contents

• Cover
• Half-Title
• Title
• Copyright
• Contents
• Contributors
• Introduction: Medical Cannabis: Critical Issues and Perspectives for Human Service Professionals
• PART ONE The Context of Cannabis: Culture, Clashes and Commerce
• PART TWO Cannabis as Medicine: Research, Practice and Future Directions
• PART THREE In Their Own Voice
• Appendix
• Glossary
• Index