Curious about the varying types of cannabis, the health benefits and risks, and the physiological effects? Learn more about cannabis and its application in healthcare and the risks associated with this plant that is growing in popularity everyday.
Cannabis is a flowering plant indigenous to Central Asia. There are three common classifications - cannabis sativa (c-sativa), cannabis indica (c-indica) and hemp, which is a sub-type of c-sativa . Cannabis is cultivated for use in a variety of commercial products including food, medicine, nutrition, clothing, textiles, biofuel, food, animal feed, cordage, building materials and plastics (1). The plant material (stock, stem, seed, leaf, etc.) is primarily used for industrial products, while the oil extract (cannabinoids and terpenes) is primarily used in nutritional and medicinal products.
A pure c-sativa plant may grow 4-8 feet high and has a long stem and large narrow bladed leaves. It produces a long narrow bud and typically has a lower tetrahydrocannabinol (THC) content and higher cannabidiol (CBD) content (6).
A pure c-indica plant may grow 3-4 feet high and is bushy with short, wide leaves. It produces a wide dense flower and typically has a higher THC content and lower CBD content (6).
Hemp is a subtype of c-sativa and may grow to be 10-12 feet high and has a thick stock, long stem and long narrow leaves. Hemp has a very low THC content and a high CBD content and has long been cultivated for the industrial use of its plant material and biomass.
Although cannabis is cultivated for a variety uses, the health benefits of its oil extract have taken center stage over the last few years. Researchers have been able to identify over 113 different cannabinoids and over 100 different terpenes that are produced by the cannabis plant (5). The most well-known compounds are cannabidiol (CBD) and tetrahydrocannabinol (THC). These compounds are found in all types of the cannabis plant, and through selective breeding cultivators can produce plants with different concentrations of CBD and THC.
Cannabidiol - CBD is the most abundant cannabinoid found in the cannabis plant. It makes up about 40% of the cannabinoid extract produced by the plant (2). CBD can be administered through oral ingestion, inhalation, nasal spray, topical lotion, or suppository.
When administered orally about 15% of the drug will make it to the bloodstream unchanged. When inhaled this number doubles to around 30%. This is known as bioavailability, which is the percentage of the drug in the bloodstream that remains unchanged after administration. The half-life of CBD is reported to be about 9 hours, which means that 50% of the drug has been eliminated from the body after 9 hours of its administration. The half-life and bioavailability of a drug are important factors in determining the dose, route and frequency of use.
CBD interacts with neurotransmitters and endocannabinoid receptors found in the central nervous system, peripheral nervous system, immune system and spleen (9,12). The extent of this interaction is not fully understood, however current research suggests that CBD partially binds with CB1 receptors found in the basal ganglia, limbic system, hippocampus and with CB2 receptors found in the immune system and spleen (8,12).
The physiological effects produced by the binding process are what make CBD medically beneficial. CBD is reported to help reduce the symptoms of nausea, anxiety, inflammation and muscle spasticity (10). Additional studies report conclusive evidence that CBD acts as a neuroprotective antioxidant (24,25). CBD recently gained approved by the Federal Drug Administration (FDA) as an anticonvulsant for the treatment of two rare forms of epilepsy.
Research also indicates CBD is a serotonin 5-HT1A receptor agonist. The 5-HT1A receptor impacts several physiological functions in the body including modulation of serotonin and dopamine , which may explain CBD’s reported anti-anxiety and anti-depression benefits (4).
Additional research suggests that CBD is an antagonist to THC, which means it inhibits THC from binding with neurotransmitter receptors. By doing so, CBD may counteract the common side effects of THC use, which may include short term memory loss and cognitive impairment (11). Studies indicate CBD is well tolerated with reported side effects that may include diarrhea, tiredness or change in appetite (13).
Tetrahydrocannabinol – THC is a fat-soluble cannabinoid found in the cannabis plant. It is the primary compound that causes the psychoactive (high feeling) effects associated with cannabis use. It can be administered through oral ingestion, inhalation, topical cream, transdermal patch, nasal spray or suppository.
When THC enters the bloodstream it makes its way to the brain and binds with cannabinoid receptors primarily located in the central nervous system. These receptors are prevalent in areas of the brain that affect body coordination, learning, memory, stress control, higher learning, cognitive function, emotional response, fear, peripheral sensations, sleep and nausea (23).
THC has an elimination half-life range of 2-48 hours and its bioavailability is estimated to be 10-35% when administered through inhalation and 6-20% when taken orally. Users often report more intense reactions to THC when taken orally. This is most likely due to enzymatic changes to the THC compound that occur during the digestive process resulting in either increased receptor affinity or increased bioavailability of the THC compound. In most cases, users report a significant reduction in the effects of THC after 2-8 hours of administration. This time will vary depending on the amount and manner of administration, the frequency of use and the tolerance level of the user (14,15).
Studies suggest that THC in combination with CBD may be effective in reducing muscle spasticity, centrally mediated pain, and painful spasms. There is also sufficient evidence to suggest that, THC combined with CBD, acts as a neuroprotective antioxidant within the body and that these antioxidant properties were demonstrated to be superior to the antioxidant properties of vitamin E and vitamin C (24,25).
Cannabis intoxication in association with short-term use of THC has been shown to negatively impact memory, attention span and physical motor skills (19). Long-term use of THC has been shown to have similar negative effects and may result in habituation requiring the user to increase the strength and quantity of THC to obtain the desired effect.
Recent studies report that 10-20% of cannabis users become dependent (17). Dependency is different than addiction and is classified by the Diagnostic and Statistical Manual of Mental Health Disorders (DSM) as “Cannabis Use Disorder” (18). Cannabis dependency is reported to be less severe than that observed with cocaine, alcohol or opiates (20). Studies suggest strongly that early age onset and long-term use of THC may contribute to mental health problems and physical and motor disorders (21). And most recently, a 2017 study reported clear evidence that long-term use of cannabis increases the risk of psychosis (22).
The cannabis plant is a rich and diverse resource and can be used in over 2500 different commercial products. As more research demonstrates the health benefits of CBD, its use in the medical and supplemental health markets have been on the rise in the US over the last decade.
The FDA recently approved a cannabis derived drug produced by GW Pharmaceuticals for the treatment of two rare forms of epilepsy. This is a big step forward in the area of cannabis research and development, which may bring about the expanded and more target use of cannabinoids, for the treatment of medical conditions.
It is clear that not all cannabinoids are beneficial. The long-term use of THC has been shown to have significant adverse effects and often results in habituation and dependency. This is especially true with early age onset of use. This is an alarming fact as more states approve medical and recreational cannabis. As the drug becomes more commercially popularized its use will likely increase amongst the younger population.
While regulated use of cannabis for medical purposes offers patients suffering from chronic conditions additional treatment options; recreational use for increasing a state’s tax revenue seems reckless given the potential downside associated with early onset use, the adverse effects of long-term use and the unknown social consequences associated with more users.
If you or a loved one is interested in medical marijuana for a chronic condition and live in the State of Florida, contact THC Physicians to learn more about how it may help.
1. Campos AC, Moreira FA, Gomes FV, Del Bel EA, Guimarães FS (December 2012). "Multiple mechanisms involved in the large-spectrum therapeutic potential of cannabidiol in psychiatric disorders". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences (Review). 367 (1607): 3364–78
2. Stockings E, Zagic D, Campbell G, Weier M, Hall WD, Nielsen S, Herkes GK, Farrell M, Degenhardt L (July 2018). "Evidence for cannabis and cannabinoids for epilepsy: a systematic review of controlled and observational evidence". J. Neurol. Neurosurg. Psychiatry. 89 (7): 741–753
3. Russo, Ethan B (2011-08-01). "Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects". British Journal of Pharmacology. 163 (7): 1344–1364
5. Karl W. Hillig; Paul G. Mahlberg (2004). "A chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae)". American Journal of Botany.
6. Tourangeau, Wesley (2015), "Re-defining Environmental Harms: Green Criminology and the State of Canada's Hemp Industry", Canadian Journal of Criminology & Criminal Justice, 57 (4): 528–554
7. Laun AS, Shrader SH, Brown KJ, Song ZH (June 2018). "GPR3, GPR6, and GPR12 as novel molecular targets: their biological functions and interaction with cannabidiol". Acta Pharmacol. Sin
8. Rogers, Nala. "Cannabinoid receptor with an 'identity crisis' gets a second look". Nature Medicine. 21 (9): 966–967. doi:10.1038/nm0915-966
9. Pertwee RG (January 2008). "The diverse CB1 and CB2 receptor pharmacology of three plant cannabinoids: ?9-tetrahydrocannabinol, cannabidiol and ?9-tetrahydrocannabivarin". British Journal of Pharmacology. 153 (2): 199–215
10.Iseger, TA; Bossong, MG (March 2015). "A systematic review of the antipsychotic properties of cannabidiol in humans". Schizophrenia Research. 162 (1–3): 153–61
11.Pacher, P.; Bátkai, S; Kunos, G (2006). "The Endocannabinoid System as an Emerging Target of Pharmacotherapy". Pharmacological Reviews. 58 (3): 389–462.
13.ffland K, Grotenhermen F (2017). "An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies". Cannabis Cannabinoid Res. 2(1): 139–154. doi:10.1089/can.2016.0034
14.Grotenhermen, F (2003). "Pharmacokinetics and pharmacodynamics of cannabinoids". Clin Pharmacokinet. 42 (4): 327–60.
15.Choices, N. H. S. (2016-12-12). "How long does cannabis stay in the body after smoking? - Health questions - NHS Choices". Retrieved 2017-01-0
16."PDSP Database – UNC". NIMH Psychoactive Drug Screening Program. Archived from the original on 8 November 2013. Retrieved 11 June 2013
17.Borgelt LM, Franson KL, Nussbaum AM, Wang GS (February 2013). "The pharmacologic and clinical effects of medical cannabis". Pharmacotherapy(Review). 33 (2): 195–209
18.Gordon AJ, Conley JW, Gordon JM (December 2013). "Medical consequences of marijuana use: a review of current literature". Curr Psychiatry Rep(Review). 15 (12): 419
19.Sagie S, Eliasi Y, Livneh I, Bart Y, Monovich E (2013). "[Short-and long-term effects of cannabinoids on memory, cognition and mental illness]
20.Budney AJ, Roffman R, Stephens RS, Walker D (December 2007). "Marijuana dependence and its treatment". Addict Sci Clin Pract (Review). 4 (1): 4–16
21.Hoch E, Bonnetn U, Thomasius R, Ganzer F, Havemann-Reinecke U, Preuss UW (2015). "Risks associated with the non-medicinal use of cannabis". Dtsch Arztebl Int(Review). 112 (16): 271–8