Understanding Medical Cannabis (Marijuana)
What is marijuana?
Marijuana consists of the dried leaves and flowers of a plant called Cannabis. There are two main types (species) of plants used as medical marijuana, Sativa, and Indica. In the U.S., Federal law prohibits the use of cannabis, however many states have legalized cannabis or the chemicals found in cannabis, called cannabinoids and terpenes.
Many people think of marijuana or cannabis as a plant used to get “high.” The reality is that the compounds found in the plant can be tailored or taken out to lessen or eliminate the psychoactive effects (“high”). Let’s review the compounds found in cannabis and how they can be used to relieve a variety of symptoms.
Cannabis Plant Species
For many years, the species (or kind) of the cannabis plant, Sativa or Indica, has been used to predict how the plant will affect you. Sativa plants grow in moist regions and can be described as tall and skinny with long, thin leaves. Indicas, on the other hand, grow in very dry or arid regions and produce a shorter, stubbier plant with wide leaves to catch any moisture available. Sativa species are said to be more uplifting and energizing, while Indica species are more relaxing and calming, some even sedating. The reality is that most cannabis is a hybrid (mix) of the two, and more recent chemical testing of the species found these generalizations to be untrue. Each product can affect different people uniquely based on their body’s biology and tolerance, along with the terpenes produced by specific strains.
What are Cannabinoids?
The cannabis plant contains more than 110 chemical compounds called cannabinoids, and more that we don’t know about yet. Of these, 2 have been the focus of most studies on medical use: THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol). These chemicals have effects on the body much like medicines do. They can affect the central nervous system and the immune system in several different ways:
- THC is the part of cannabis that has psychoactive effects – it can produce the “high” feeling. It has been found to help with pain, nausea, and insomnia.
- CBD is the part of cannabis that has been found to help with anxiety, inflammation, and pain. It has no psychoactive effects.
The Balance of CBD and THC
Cannabis strains are grown to have different amounts of THC and CBD, to meet the different needs a person may have for cannabis. This is called the THC: CBD ratio. THC and CBD have a synergistic effect on each other, meaning they work better together than either does alone. In general, the products fit into 3 groups:
- THC dominant: these strains contain less CBD and can cause a strong “high,” sleepiness and anxiety. The degree of “high” can vary greatly based on the patient’s tolerance. For this reason, it is often recommended to start with a low dose and work up.
- CBD dominant: these strains have less THC when compared to the CBD, allowing patients to have a clear head which can be important to maintain your normal roles & responsibilities. When the CBD outweighs the THC, much if not all, of the psychoactive effects of the THC, will be negated.
- Balanced CBD and THC: these strains/products tend to have a slightly higher amount of either component, but are more balanced than either of the two previous. When in like amounts, here again, the CBD will cancel much of the psychoactive effects of the THC compound.
How do Cannabinoids work?
We have receptors throughout our body that make up the endocannabinoid system (ECS). This is one of the most widely distributed receptor systems throughout our bodies and is likened to a fingerprint, meaning it is unique to each of us. Our bodies naturally make “endocannabinoids” that interact with the ECS receptors. The ECS system helps our body maintain balance or homeostasis. Plant-derived cannabinoids are also able to interact with these receptors, working alongside our body’s natural system.
The two major ECS receptors are CB1 and CB2 receptors. CB1 receptors are most commonly found in the nerve cells of the brain and spinal cord. It is these receptors that THC interacts with to cause its psychoactive effects or “high.” CB1 receptors can also be found in the spleen, GI tract, reproductive and urinary systems, endocrine system and white blood cells. The fact that these receptors are found in so many areas of the body explains why cannabinoids can be used in a variety of ailments. CB2 receptors are commonly found in the immune and hematopoietic (blood cell) systems. They are also found in the brain to a lesser degree than CB1 receptors.
What are Terpenes?
Terpenes are compounds or essential oils found in many plants and some insects. They contribute largely to the taste and smell of the object. Terpenes bind to receptors like cannabinoids, causing certain effects in the body, and can act directly on tissues and cells in the immune system. There are hundreds of terpenes, but a handful are more common. Many cannabis analysis labs report terpene content on product labels, allowing you to choose a strain based on the terpenes it produces. The more common cannabis terpenes include Myrcene, Terpinolene, Limonene, Humulene, Pinene, Linalool, and Caryophyllene.
- Myrcene is the most common terpene in cannabis and is thought to have a calming effect. It tends to be stronger in the Indica species. Myrcene is found in mangos, lemongrass, and thyme. It can be effective as an antioxidant and anti-inflammatory. This makes it useful in treating pain conditions caused by inflammation.
- Terpinolene is thought to have energizing effects, is common in the Sativa species. It may function as an antioxidant and antibacterial agent. It is found in plants such as lilac, nutmeg, and cumin.
- Limonene is found in many citrus fruits, rosemary, juniper, and peppermint. It is thought to elevate mood and provide stress relief. It may work as an anxiolytic, anti-depressant, and anti-inflammatory agent.
- Humulene can be described as woody or earthy and is found in hops, sage, and cloves. It may work as an anti-inflammatory, analgesic, and anti-bacterial.
- Pinene is found in pine needles, rosemary, basil, parsley, and dill. It can promote alertness and memory retention, while also counteracting some of the THC effects. It may work as a bronchodilator, analgesic, anti-inflammatory, anxiolytic, and is gastroprotective.
- Linalool, commonly found in lavender and birch bark, offers mood enhancement and can be sedative. It tends to be more pronounced in the Indica species and may be used to treat anxiety, depression, insomnia, pain, inflammation, and neurodegenerative disorders.
- Caryophyllene is used for pain, inflammation, anxiety and stress disorders, depression, and ulcers. It may be helpful in opioid withdrawal symptoms as well. Caryophyllene is found in common kitchen spices such as black pepper, cloves, cinnamon, and oregano.
Terpenes appear to work together with cannabinoids to promote the unique effects of each individual compound. This is known as the “entourage effect.” Some studies have found that using one cannabinoid, without the entourage of compounds found in the cannabis strain it came from, results in fewer benefits.
What do people with cancer use cannabis for?
Cannabis products are most often used for symptom management in people with cancer. It may be used to help manage pain, nausea, anxiety, and insomnia, and can stimulate the appetite when weight loss is a concern. Several of cannabis’ compounds are being studied for their ability to inhibit cancer cell growth, though research is needed to understand how it works and which specific products and cancer types will have the best results.
How is cannabis taken?
Cannabis can be taken or used in its whole plant form (typically the flowers or “buds” of the plant) or compounds taken from the plant (THC or CBD). It can be consumed in 3 main ways: inhalation (through smoke or vapor), consumption (by mouth), and topically. It is important to point out that different states have legalized different methods or products, so you may not have all of these options available where you live.
Inhalation of Cannabis
Cannabis can be smoked in a pipe, hookah, or rolled into a “joint” (rolled in cigarette paper) or “blunt” (rolled in tobacco paper). Cannabis can also be inhaled in vapor form – called vaporized. This is done using a vaporizer, which heats the product enough to release the cannabinoids but does not ignite or burn the product. Vaporization has shown to be a cleaner method of inhaling cannabis as there is no smoke or carcinogens being inhaled. There have been health concerns around vaping marijuana in the news, but it is important to remember these health problems occurred using unregulated products that had other toxic ingredients.
There are many different types of vaporizers, which use a variety of cannabis forms such as the bud of the plant, an oil or wax/resin (also called shatter). These may be used by adding them to the vaporizer or may come in pre-filled cartridges that fit in the vaporizer.
Vaporization tends to work more quickly than oral methods – in as little as 1 to 15 minutes. It generally lasts 1-3 hours, which is shorter than ingested methods. During vaporization, CBD and THC are inhaled into the lungs along with other compounds. This can be a concern, particularly for people with lung disease or cancers affecting the lungs.
Taking Cannabis by Mouth
There are a number of ways to take cannabis by mouth such as tinctures, capsules, oils, and edibles.
Tinctures are liquids that are mainly used sublingually, meaning it is placed under the tongue and allowed to sit for about 30 seconds. This allows it to be quickly absorbed and can start working in 15-30 minutes. Sublingual cannabis tends to last about 2-4 hours in the body. A tincture can also be swallowed directly or placed in a liquid beverage, though this takes longer to work (30-90 minutes).
Oils can be used sublingually, swallowed or taken in a capsule/softgel. Cannabis oils, tinctures, flower, or ingredients infused with cannabis (such as butter or vegetable oil) can be used to make foods or drinks that produce the effects of cannabis. These are called edibles. Consuming cannabis in this way will produce an effect in about 30 to 90 minutes, but will offer the longest duration of action – 4 to 8 hours.
Using Topical Cannabis
Topical cannabis is made by heating the cannabis flower to activate the cannabinoids and making an extract from this. This can be made into a lotion, cream or ointment. These can provide pain relief to the area they are applied. The cannabinoids are not absorbed into the bloodstream, so there is no risk of psychoactive effects or getting high. Topical applications tend to work quickly – anywhere from 1 to 10 minutes and last up to 5 hours.
Another “topical” method is known as transdermal. These compounds are absorbed into your bloodstream. THC is absorbed, so there is a risk of psychoactive effects. These are available as either THC alone or a balanced formula containing both THC and CBD.
How does cannabis from a dispensary differ from recreational marijuana?
A dispensary has trained staff to assist you in selecting products. They can help you choose the right product and ratio of THC: CBD for your needs. Marijuana from a dispensary is highly regulated and labeled with ingredients and amounts so you can understand and be comfortable with what you are using. Recreational marijuana is not regulated…you cannot be sure what you are getting, if there are contaminants, or if it is safe.
What about all the CBD products I see in the mall/grocery store/etc?
CBD products found in stores and online are made from the hemp plant, which contains less than 0.3% THC and will not cause any “high” effect. The main difference between hemp and marijuana is that hemp produces much less THC and does not contain many of the other helpful compounds found in cannabis. For this reason, CBD oil from hemp may not have the same effects as CBD from cannabis.
When purchasing CBD oil from a cannabis dispensary, you will need to look at the THC content. The staff in a shop can help you determine how much THC is best for your needs. However, remember that every person’s body will react differently and it may take a little experimenting before you find the best product for your needs.
CBD and THC oils generally come in 3 types:
- Full-spectrum – this contains all the compounds found in the source product, such as THC, CBD, terpenes and other cannabinoids.
- Broad-spectrum – contains many of the compounds from the source plant, but THC is removed.
- CBD isolate – contains only CBD with all other compounds removed.
How can I access cannabis?
Unfortunately, there is no one answer to this. Each state has its own laws and processes for gaining access for medical use. In a few states, cannabis is legal for all adults. In most states, you must have a health condition on that state’s list of conditions to qualify for medical cannabis. If you have a qualifying condition, you will need to obtain a medical marijuana card to visit a dispensary (the place cannabis products are sold), purchase and carry products. In some states, you are also able to grow small amounts of cannabis.
The first step is to visit a provider registered with your state who is able to recommend or certify you for medical cannabis use. In some states, this must be a doctor (MD or DO), while other states allow nurse practitioners (NPs) and physician’s assistants (PAs). You can learn more about finding a provider in the links at the end of this article. Since marijuana is federally illegal, they cannot write a prescription as you are used to with other medications. Instead, the provider recommends marijuana for your situation and may provide some guidance as to the type that might benefit you most. For instance, a person with breathing problems may be advised to not use vaporized cannabis. You will then need to follow your state’s process for obtaining your card.
How can I learn more?
There are many good resources for information about medical marijuana and CBD. Regulations differ from state to state, and you must abide by the laws in your state. Many states do not allow reciprocity, meaning you cannot use your card to purchase medicinal cannabis outside of the state where you are registered. There may also be legal concerns with traveling across state lines with products.
If you are interested in learning more, the list below can help you get started in your research:
- Americans for Safe Access – Information about each state’s laws and rules and other resources. https://www.safeaccessnow.org/becoming_a_state_authorized_patient
- Cannabis and Cannabinoids from the National Cancer Institute. https://www.cancer.gov/about-cancer/treatment/cam/patient/cannabis-pdq
- Society of Cannabis Clinicians. https://www.cannabisclinicians.org/resources/patient-resources/
- American Academy of Cannabinoid Medicine. https://aacmsite.org/
- Leafly – This website sells products, and while OncoLink does not endorse their products or product/dispensary recommendations, they have a wealth of educational information on their website. https://www.leafly.com/news/cannabis-101
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