Why Marijuana Medicine Works

Looking at cannabis as whole plant medicine, the author examines the many healing components throughout the plant, from flowers to roots, from cannabinoid acids to alkaloids. In this in-depth guide to cannabis therapy, written for both health practitioners and those looking for self-care methods, herbalist and holistic healer Wendy Read provides a complete look at why marijuana medicine works, its medical and spiritual uses throughout history, and how to develop a personalized healing plan. She explores the endocannabinoid system (ECS) of the body and how phytocannabinoids interact with it.

Cannabinoids and the Endocannabinoid System.

Before we can contemplate marijuana as medicine, we need to understand the complex endocannabinoid system (ECS). The ECS, found in all animals, is the physical avenue by which marijuana interacts with our bodies, our minds, and our spirits, writing the codes for health and bliss.

The story of the ECS begins 34 million years ago when life as we know it began in the great Mother Ocean. The first beings, enclosed in a single cell, were free-floating and self-contained. They could not survive alone, however. Like us, they needed communication with others to thrive. Even at the beginning all life was connected, albeit with invisible threads, in a magnificent energetic web.

Exactly how were those cells talking with each other as they were propelled through the chaotic tides? They were sending and receiving tiny packets of chemicals produced within their membranes.

Can you imagine each cell opening its doors to receive news brought on the current, like a housewife welcoming gossip from a door-to-door fruit seller? Possibly the updates were about the usual things, like the weather or where to find favorite foods. Perhaps they, too, warned each other about which neighborhoods to avoid due to unfavorable conditions or unsavory characters. And the chemical messages themselves? They were cannabinoids, or more accurately, phospholipid cannabinoid precursors.

When I ask my students what a cannabinoid is, few can answer. But when I ask for an example of a cannabinoid, inevitably they shout out “THC!” Short for tetrahydrocannabinol, THC is the most famous cannabinoid in the world. THC is a phytocannabinoid, created by a plant, rather than an endocannabinoid, which are created by animals. The two kinds of cannabinoids have slightly different structures, but share many functions within an animal system.

Today’s cannabinoids are still tiny, comprised of a molecular chain of a mere twenty-two to twenty-five carbon atoms. Cannabinoids’ main function is to carry directions and information between animal cells. They are often classified as neurotransmitters because they send signals through and between the nerve cells that make up the nervous system. Neurotransmitters, including serotonin and dopamine, the cannabinoids’ more famous cousins, are well-known for the powerful role they play within the body and mind. For example, pharmaceutical antidepressants called serotonin reuptake inhibitors, or SSRIs, change the way our bodies process serotonin. As anyone who has used them can attest, their effects on the body and the emotions can be extreme. The feeling a mother has when cradling her infant is the work of oxytocin, another neurotransmitter. That feeling of well-being some experience when eating chocolate and the devastatingly intense grief when a loved one dies are both a result of neurotransmitters.

As it turns out, cannabinoids control the nervous system. In addition to a multitude of other duties, they rule over the other neurotransmitters. For example, cannabinoids indirectly increase dopamine levels by blocking the action of another neurotransmitter, GABA, which reduces the amount of dopamine released. When GABA is blocked by marijuana compounds, the result is an increase in the amount of dopamine released. Cannabis is nature’s answer to SSRIs, but unlike SSRIs, she follows the edict “First, do no harm” and brings the body into balance without unhealthy side effects or withdrawal symptoms.

How did we get to the complex ECS from those primordial single- celled beings? As those cells were floating around, they would bump into each other, perhaps even seeking each other out. At some point, they started to realize the advantages of floating through life together and decided to form colonies. They drifted around like little rafts, with those in the middle well protected from outside influences like viruses and other predators, and those on the edges having first access to food. When some cells perished, cannabinoid signals were sent out, triggering others to divide into two daughter cells, thus replenishing the colony.

Eventually, for protection, some colonies surrounded themselves with a membrane and became, in essence, a gated community. Cells worked together and consciously chose what entered and what exited, essentially taking in groceries and sending out the garbage. Just as a baker or weaver provides a specific service to the village, cells within the colony began to specialize and differentiate from one another by turning on only a small section, or sequence, within their protein-producing DNA. Some turned into skin cells, others feather cells, others became brain cells, and so forth. They continued to use cannabinoids to communicate.

All animals produce cannabinoids that control life’s functions. Created on demand, they leap between the axon of one nerve to the dendrite of the next. They float through our blood until a cell fishes them out of the slipstream and pulls them inside. There, the cannabinoids deliver direction to stimulate or (more often) inhibit the cell’s function, speeding or slowing, starting or stopping pathways of creation or courses of destruction. Together, these millions of tiny alterations throughout our systems continually guide us toward homeostasis, trying to keep us in balance.

Just as we raise a flag on our mailbox to signal outgoing mail, cells throw up a flag on the outside of their membranes when they need to take in nutrients, expel waste, or receive directions for their work. These flags, aptly named receptors, are the fishhooks, and they are baited to attract only a specific kind of chemical from the stream. Once caught, a porthole in the cell membrane opens, and the cannabinoid or other chemical is reeled in.


Certain “magical” plants, animals, and funguses have always provided spiritual healing to animals. The witches, prophets, and seers of indigenous spiritualities have ancient relationships with beings like peyote cacti, psilocybin mushrooms, herbs like ayahuasca and ibogaine, and many others. These beings help them heal themselves and others by connecting them with the invisible world of energy that surrounds us. On a deep level, humans have always known about the magical effects of marijuana. Unfortunately, these magical substances have been demonized by cultural authorities and driven underground off and on for thousands of years. At this time in history, many are coming back into the light and are beginning to pique the interest of Western medicine.

Take, for example, the opium poppy. Used in Asia for thousands of years and brought to the West during the mid-nineteenth century Opium Wars between China and England, this delicate flower has one of the strongest known pain-relieving effects in the world, and she also provides a spiritual sense of well-being.

In the 1970s Western scientists became curious about how she works in our system. With new technology they were able to isolate opium molecules and mark them with a radioactive dye. When injected into an animal, they could see them course through an animal’s system and note where they were absorbed.     They discovered and mapped the system of opium receptors in animals. But why do animals, for which poppies are not a food source, produce pain reduction receptor sites specific for opium molecules? Continuing investigations revealed that these receptors are actually designed to capture opium molecules produced by the animals themselves.

Called endorphins (from endogenous meaning “produced within” and morphine, a pain-relieving alkaloid made by poppies), these chemicals produced by our bodies help block pain signals and offer a sense of peace and well-being. When our endorphins prove insufficient for intense pain, poppy plants act as a perfectly designed supplement. The discovery of the poppy-activated endorphin system spurred scientists to search for other systems activated by naturally occurring drugs.

Although THC was discovered in 1964 by Israeli researcher Raphael Mechoulam, Ph.D., it was not until three decades later that his team searched for endogenous THC receptors in animals. The only well-known use of weed at that time was to get people high, so they hypothesized that they would find receptors for THC in the brain. They synthesized cannabinoids, dyed them, and injected them into animals to trace their path- way. They were right about the brain, of course, but were surprised when they also found receptors throughout the entire central nervous system.

Scientists knew that the fact that THC made people high indicated that, like opium, it could cross the blood-brain barrier. The blood-brain barrier is a protective lining that surrounds the central nervous system (the CNS) and forms a strong line of defense between the blood circulating through our bodies and the fluid that circulates within the CNS. It controls what passes between the two and, for example, allows animals to endure extreme infections and other toxic insults without brain damage. Most pharmaceutical drugs, even antibiotics and cancer treatments, are too toxic to be allowed through the barrier, yet our central nervous system readily invites marijuana into its inner sanctum. This is partly why   cannabis provides such a myriad of therapies for the mind.

When Mechoulam found the first endocannabinoid, meaning a cannabinoid endogenous to animals, in 1992, he demonstrated his immediate understanding of its power when he named the molecule anandamide. Ananda means “bliss” in Sanskrit, the language of the Vedas, the world’s most ancient religious texts. They are dedicated to the worship of Soma, a deity, and a cannabis tea. (The full story is told in chapter 10.) Upon discovery of a second endocannabinoid, Mechoulam forsook all sense of poetry and named it 2-arachidonoyl glycerol, or 2AG for short. Since then, two more endocannabinoids, lysophosphatidylinositol and virodhamine, have been discovered, and it is safe to assume that more will be found soon.

Excerpt from: Cannabis Therapy by Wendy Read with permission of the publisher Inner Traditions

ISBN: 9781644118504, May 2024. https://www.innertraditions.com/books/cannabis-therapy.

Wendy Read is a certified herbalist, holistic massage therapist, and plant spirit healing practitioner with a bachelor’s degree in biochemistry from California State University, Chico. She has studied with herbalists and shamanic healers in Mexico, Guatemala, Swaziland, South Africa, Senegal, and the United States. Since 2005 she has taught at Motherland Sanctuary and many other herbal schools and symposiums. A spiritual counsellor and founding minister of the Caretaker’s Garden, she also has a clinical, holistic healing family practice. https://www.caliheal.org/