Curious about Cannabis? The recent decade has seen increased legal access to medical and recreational cannabis. California became a recreational cannabis state in 2019. Since then, we notice that more of our clients are using cannabis products, and have questions about their uses and effects. Print and online information can vary in accuracy, and important details can be difficult to find. This blog post briefly summarizes pertinent information about cannabis. Its intention is to inform and educate, and not to advise. We recommend you communicate with your doctor if you wish to use cannabis as a remedy for an ailment. Read on to find out more about this interesting botanical, and how it can affect pain, inflammation, sleep, and more. 

First, some history and perspective…

As it turns out, humans have been using cannabis for thousands of years. Cannabis was found in the bag of a Chinese medicine man dating back to ~ 3,000 BC. There is also evidence of cannabis use in India in ~1,700 BC, and in Egypt ~ 1,500 BC. Cannabis was brought to England during the Victorian era. It appeared in Western medicine in the 1840’s, being used to treat pain, inflammation, seizures, spasms, and as a sedative. Most major US pharmaceutical companies had some version available in the early 1900’s. The Prohibition era ushered in a law that taxed doctors for prescribing cannabis (this was opposed by the American Medical Association at the time). In 1951, cannabis was included in the category of “narcotic” drugs. In 1970, cannabis was categorized as a Schedule I substance (the most restrictive category) in the Controlled Substances Act. Schedule I drugs are defined as those with no accepted medical use and high potential for abuse, and only restricted research is allowed. Other examples of Schedule I substances include LSD, heroin, and ecstasy. Hemp also ended up in this group because it is related to cannabis, even though it has no psychoactive effect.

Currently, medical cannabis is legal in 33 states. Recreational cannabis is legal in 16 states and the District of Columbia. Cannabis remains fully illegal in 6 states. California allows both medical and recreational marijuana.

Getting “high” is a low priority for seniors who use cannabis

In 2018, a survey performed by BDS Analytics and AARP found that aging adults tend to use cannabis for specific purposes at certain times of the day, such as managing pain, or before bedtime to help them sleep. This study surveyed individuals 50 years old and older in 26 states where medical cannabis was legal. Of the 11,600 respondents, 12% used cannabis and another 41% reported that they were considering cannabis. The reported purpose of use was as follows:

• 19% for “pain relief”
• 16% to “relax”
• 9% to “sleep better”
• 9% for “treating a health problem”
• 6% “to get high or stoned”

The survey participants also reported their method of use: 81% were smoking or vaping, 40% were using edibles, and 20% were using topical salves. Overall, this report indicates that aging adults use cannabis because it is helpful in managing some conditions, including pain.

How does cannabis effect the human body?

All vertebrates have an endogenous (internal) cannabinoid system (ECS). The cannabis plant is rich in Phytocannabinoids, the plant version of cannabinoids. These plant cannabinoid compounds interact with the ECS in humans.

Components of the ECS are found in multiple areas of the body. To date, we do not fully understand how the ECS works. Research in this area has been limited, largely because of the Schedule I status of cannabis. However, limited research shows that the ECS may have a role in regulating

• Appetite and feeding
• Memory, mood, and stress
• Blood pressure
• Emesis (vomiting)
• Movement

Ever wonder why cannabis edibles are so often associated with chocolate?

There are two main cannabinoid receptors in human tissue: CB-1 (largely found in the brain and central nervous system, but also in the lungs, liver, and kidneys), and CB-2 (found in peripheral tissue and the immune system). Cannabinoid receptors are available for cannabinoids, generally naturally inside the body (endocannabinoids), or introduced into the body as cannabis or a related synthetic compound. Neurotransmitters facilitate the availability of the cannabinoid receptors (like opening and closing a gate). One of those neurotransmitters is anadamide. Cacao is rich in anandamide, and chocolate is made from cacao. Hence the ubiquitous special chocolate brownie.

Here’s another interesting fact – it is not possible to fatally overdose on cannabinoids, and here is the reason why. While cannabinoid receptors are found in different parts of the brain, they are not found in the brainstem which is responsible for controlling breathing and heart rate. This means that cannabinoids are not able to shut down the body’s breathing and circulatory system. Compare this to prescription opioids. Opioid receptors are found throughout many areas of the brain, including the brainstem, and an overdose can cause breathing to shut down completely or depress the brain’s mechanism that regulates the heart and blood circulation. Prescription painkillers cause thousands of overdose deaths a year. In 2018, 67,367 Americans died from opioid overdoses.

So back to the plant: phytocannabinoids

There are more than 70 unique phytocannabinoid compounds, but the most abundant and commonly known are THC (tetrahydrocannabinol) and CBD (cannabidiol). In the raw plant form, THC exists as THCa, and CBD as CBDa. Carboxylation needs to occur (some form of heating process) for THCa to become THC, and CBDa to become CBD. THC has psychoactive effects (results in feeling “high” or “stoned”), whereas CBD does not.

THC binds to CB-1 and CB-2 receptors.  THC reduces nerve pain, is a nerve regulator, and it has psychoactive effects.

CBD binds to CB-2 receptors. CBD decreases pain, decreases inflammation, and has no psychoactive effects.

Treatment applications for cannabis

The legalization of cannabis, particularly recreational cannabis, has resulted in a plethora of advertisements for many claims and reported uses for cannabis, and an outpouring of new products on the market. Because the endocannabinoid system is integral to so many other systems in our bodies, the potential for therapeutic effects appears to be good. However, at this point, there has been scarce data and research around cannabis, and it uses and effects. This, again, arises from the Schedule I classification of the substance. Historically, it has been exceedingly difficult to get federal funding to study the therapeutic potential of cannabis. Further complicating the matter, some of the early studies regarding cannabis are now less relevant because cannabis growers in recent decades are cultivating strains of cannabis with much higher concentrations of cannabinoids, especially the psychoactive THC. The National Institute of Health (NIH) reports that in the early 1990’s, the average THC content in confiscated cannabis samples was less than 4%. In 2018, it was more than 15%. As they say, cannabis today is “not your mother’s MaryJane.”

What we do know from research so far

With “conclusive” evidence, cannabis --

1. Reduces pain, particularly neuropathic pain (nerve pain) (THC > CBD)
2. Decreases inflammation (CBD > THC)
3. Decreases muscle spasms (THC and CBD)
4. Reduces nausea and vomiting associated with chemotherapy (THC)

With “moderate” evidence, cannabis --

1. Promotes appetite and reduces excessive weight loss (e.g., with HIV / AIDS)
2. Reduces and helps manage seizure disorders (e.g., look up Charlotte’s Web, and the story of the girl behind it)
3. Improves sleep disorders

Side effects and contra-indications

Food and drug interactions appear to be extremely uncommon. As stated above, there are no known cases of a lethal dose. New users initially tend to have more side effects. Regular users develop more tolerance, but if they stop for several days, the tolerance subsides to a lower baseline. Side effects may include dizziness, lightheadedness, fatigue, drowsiness, weakness, increased heartrate (if smoked), airway inflammation (if smoked), decreased muscle control and co-ordination. Chronic excessive use in teens has been linked to mental health problems.

Is cannabis addictive?

The National Institute of Health (NIH) reports that cannabis use can lead to the development of problem use, known as cannabis use disorder, which takes the form of addiction in severe cases. Recent data suggests that up to 30% of people who use cannabis regularly have some degree of cannabis use disorder. Young people who start using cannabis before the age of 18 are four to seven times more likely to develop a cannabis use disorder than adults.

Routes of administration and effect

There are four main ways to “take” cannabis:

1. Smoking / Vaporizing: Smoking or vaping effects are felt quickly (5 to 10 minutes), with peak effect in about 30 minutes. Duration of effect is usually 2 to 3 hours. The advantage of this method is the quick effect, and the consumer can tell more accurately if the desired dosage has been taken. Disadvantages are that it is less discreet and can irritate airways.
2. Edibles (e.g., gummies, chocolate, baked into brownies, etc.). Nutrients from food entering the gut are absorbed into the blood stream and eventually pass through the liver. This takes some time. Effects are felt in 30 to 90 minutes, with peak effect in 2 to 3 hours. The duration of effect may last 4 to 12 hours. The advantage of this method is that it is discreet and easy. The most common disadvantage is over-consumption because of the delayed effect – individuals may end up consuming larger amounts of cannabis while waiting for effects to be felt.
3. Tinctures: Alcohol-based tinctures are absorbed though the mucosal lining of the mouth (preferably under the tongue). Because this avoids processing through the gut, the effects are felt much faster than edibles.
4. Topical (Salve, Patches): Topicals are absorbed through the skin. They are thought to have a local (and not systemic) effect.

Substances inhaled or eaten have a systemic effect. They enter the blood stream via the lungs or digestive system, and their effects are felt throughout the body. Substances spread on the skin surface are absorbed through the skin, and reach tissues close to that location.

A word about the extraction process

CBD and THC need to be extracted from the plant for their infusion into edibles and topicals. A cannabis extract is defined by the method through which it is made. Various solvents can be used for this process. Some solvents (e.g., butane and ethanol) can leave harmful residues. Extraction of cannabis using carbon dioxide (CO2) is considered a safe and non-toxic solvent by the Federal Drug Administration (FDA).

A word about dosage

Cannabis is a botanical. It is inherently difficult to dose accurately. There are many different cannabis strains with not only varying amounts of THC and CBD, but also several other compounds including cannabinoids, terpenoids and flavonoids. Research supports that these compounds work together to have an effect that is greater than the sum of their parts. This means, for example, that a specific amount of extracted CBD is likely more effective when in combination with some other cannabis plant compounds (e.g., THC), than in isolation. This is called the “entourage” effect. It also appears that there is a “sweet spot” when it comes to dosage, above or below which the desired effect is reduced. In California, cannabis products are required to indicate milligrams per dose or serving, and CBD to THC ratio.

Deciding why, how, and preference

1. Why: What about the ailment to be addressed is the problem? In orthopedic physical therapy, this is largely around pain, inflammation, and interrupted sleep. Also, is a local tissue or systemic effect desired?
2. How: How quickly is the effect desired? Consider the following examples:

An individual with neuropathic pain, who wakes at night in pain and cannot return to sleep, may briefly vape cannabis to obtain a rapid reduction in pain, assisting them to fall asleep again. Furthermore, the individual might sleep through whatever psychoactive effect may be part of the treatment result.

Another individual chooses a topical salve with high CBD content for a swollen finger joint or an inflamed tendon, where the desired result does not need to be immediate, but the effect should be longer lasting.

3. Preference: Is a psychoactive effect desired or not? If not, a systemic product with THC should be avoided. Others may prefer to avoid smoking or vaping because it is less discreet, or they have lung or heart concerns.

Selecting product

The trend to legalization of cannabis has resulted in tremendous growth in the cannabis industry, reminiscent to the dot com boom in the late 1990s. New companies and products have exited the market as quickly as they have appeared. It can take a bit of trial and error to find the right product, and frustrating to then discover it is no longer available. Follow your physician’s advice and recommendations. It is a safer bet to pick a product line that has been around for a while and offers a range of products in different CBD to THC ratios. Well-known brands like this are generally more consistent with their products and can be found in most dispensaries.

So, what about hemp?

Hemp is a variety of cannabis. It has been farmed as an agricultural crop, mostly for its fiber content and uses for cloth. In fact, it was considered a staple crop in the USA in the 1700s and many farmers were required to grow it. Hemp looks like the cannabis plant, just taller and skinnier, like bamboo. Hemp contains CBD, and negligible amounts of THC. The CBD in hemp is more difficult to extract than from the cannabis plant and is less plentiful (meaning more hemp is needed to produce the same amount of CBD). The CBD from hemp is the same as CBD from cannabis. In California, cannabis is heavily regulated and can only be legally sold in a dispensary. This means that CBD-only products derived from cannabis are required to be sold in a dispensary. CBD-only products derived from hemp do not share the same restriction.

Synthetic THC and CBD and indications for use

The US Food and Drug Administration (FDA) has approved THC-based medications, dronabinol (Marinol) and nabilone (Cesamet), prescribed in pill form for the treatment of nausea in patients undergoing cancer chemotherapy and to stimulate appetite in patients with wasting syndrome due to AIDS. In 2018, the FDA approved a CBD-based liquid medication called Epidiolex for the treatment of two forms of severe childhood epilepsy.

Currently a mouth spray with THC and CBD, Nabiximols (Sativex), is undergoing clinical trials in the USA. This medication is now used in several countries for the treatment of spasticity and neuropathic pain.

Medications like these are purified chemicals based on those found in cannabis. They are easier to research because they are regulated manufactured compounds, and every dose can be made reliably the same. They lack the complexity of the multiple compounds in botanical cannabis products, where consistent dosing is challenging. As discussed above, there is not enough research evidence at this time to know what influence these compounds may or may not have in the overall therapeutic effect.

Interested in learning more?

Contact your physician for further information and guidance.

There are many online resources available. Here are a few:

https://cannabis.ca.gov/

https://www.cannabisclinicians.org/resources/patient-resources/

https://medicalmarijuana.procon.org/

https://unitedpatientsgroup.com/

For those looking for a deeper dive, here are a few books to consider:

Medical Cannabis: A guide for patients, Practitioners and Caregivers. Michael Moskowitz MD. ISBN 978-1-63393-540-2

CBD: A patient’s Guide to Medical Cannabis. Leonard Leinow and Julia Birnbaum. ISBN 978-62317-183-4

Author: Kathryn Thornburg DPT, OCS, FAAOMPT

Co-owner Fyzical Grand Lake Oakland