The use of cannabis for medical purposes has gained massive attention in recent years. According to the World Health Organization, cannabis is the most widely cultivated and abused drug worldwide, with a prevalence of 2.5% of the population (as cited in Bridgeman & Abazia, 2017, p. 180). This essay will focus on how cannabis works in the human organism considering the endocannabinoid system and endocannabinoid deficiency syndrome. There are four routes of administration for cannabis used in medical practice. These routes are inhalation or vaporization, oral, topical, and rectal.
Endocannabinoid System and Endocannabinoid Deficiency Syndrome
Once the substances in cannabis, called cannabinoids, were identified, it became clear that they interact with receptors. The receptors use neurotransmission to send signals throughout the human body. When cannabinoids bind to the receptors, they change the signaling and healthy communication. Endocannabinoids (EC) are neurotransmitters found in the body that allow cannabinoids to attach to the receptors and alter the behavior. Thus, endogenous cannabinoids (ECs), cannabinoid receptors, along with enzymes that take part in endocannabinoid degradation, constitute the human endocannabinoid system (ECS). The ECS is located everywhere and helps the human body to maintain homeostasis by affecting post-synaptic neurons that release ECs (Sallaberry & Astern, 2018). The cannabinoids receptors are G-protein coupled receptors that respond immediately to the incoming signals. For example, when there is inflammation in the cut region, the lymphatic system releases white blood cells from the vessels that cause inflammation. If there is no need for an inflammatory response, the cannabinoid receptors will bind to the cannabinoids in the surrounding cells, reducing inflammation.
Two receptors play a role in pain regulation as a part of ECS, cannabinoid receptor 1 (CB1 receptor), and cannabinoid receptor 2 (CB2 receptor). Binding of CB2 receptors leads to the activation of gamma-aminobutyric acid that reduces pain. Cannabis has phytocannabinoids that can selectively bind to the receptors. Tetrahydrocannabinol (THC) binds to the CB1 receptor, while beta-caryophyllene targets CB2 receptors (Sallaberry & Astern, 2018). As phytocannabinoids are similar to ECs, receptors recognize them as native molecules. Some people lack ECSs, a disorder which is called endocannabinoid deficiency syndrome (ECDS). When there are not enough cannabinoids produced in the body, the homeostasis becomes impaired. This leads to the number of diseases related to the inflammatory response.
Routes of Administration for Cannabis
There are four routes of cannabis administration: inhalation, oral, topical, and rectal administration. Using cannabis cigarettes is the most popular way of consumption among recreational users (Sanchez, n. d.). However, it is also the most dangerous route because when cannabis and paper are burnt, their byproducts, such as carbon monoxide, can lead to chronic illnesses. Among illnesses, there are obstructive bronchitis, chronic cough, and pulmonary edema. Smoking can be replaced with a similar route, inhalation through vaporizers. This method allows cannabis to be heated up without reaching the temperature in which it decomposes to the byproducts through pyrolysis. The advantage of this route is that cannabis reaches its highest concentration in the blood after inhalation. This implies immediate medical effect, which is useful when patients suffer from acute pain and prevent overdose episodes. Moreover, the bioavailability, which is an amount of substance that enters the blood, is higher (25%) in comparison to other ways (Sanchez, n. d.). The drawback of this route is the concentration of cannabinoids in the body that may vary and depend on the doze, the temperature and duration in the device.
The next route of administration is oral, which may be submucosal and sublingual. The effect of cannabinoids taken by this route takes longer and is less intense compared to inhalation, which is a main disadvantage of this route (Sanchez, n. d.). This is because the liver cannabinoid receptors massively degrade the substance before reaching the blood circulation. However, cannabinoids for sublingual use and tinctures were observed to be absorbed much faster than other edibles. The oral route is used by patients who suffer from chronic diseases and need a continual uptake of cannabinoids. According to the study by Bruni et al. (2018), another advantage of oral administration is the presence of pharmaceutical-grade compounds that allow for accurate drug dosing. For example, oils and capsules are used because they have more precise concentration, compared to juices or teas that are more difficult to control.
Cannabinoids can be utilized in the form of creams and lotions, a topical route of administration. Although this method is becoming more popular among patients, there is no extensive research on this route. The existing studies suggest that the patches and creams have slow absorption, low bioavailability, and long-lasting but not too high effect (Sanchez, n. d.). The advantage of topical administration is that it can be used as a local anti-inflammatory agent to cure skin problems such as acne, wounds, and insect bites. According to Bruni et al. (2018), topical route is suitable for “localized symptoms, such as those found in dermatological conditions and arthritis but also in peripheral neuropathic pain for which capsaicin patches have been proposed as a second-line treatment after high quality of evidence was provided.” (p. 10) On the other hand, its low bioavailability can be ineffective for some patients with acute pain.
Like in the case with the topical route of administration, there is no thorough research conducted on the rectal one. Despite this, this method is gaining popularity among patients, because they can use high doses of the substance without significant psychotropic effect. This is because cannabinoids cannot pass through the rectal mucosa due to their hydrophobic nature. It is possible to make cannabinoids less hydrophobic by binding them to hemisuccinate. This technique allows for more efficient absorption in the rectum. However, synthetic substances are not purely phytocannabinoids, which makes it difficult to predict the organism’s effect. Although the use of cannabis through this route, at least for this time, is limited, it can still be used as a local painkiller for patients who have problems with the rectal part of the gastrointestinal tract, or for those who cannot ingest cannabinoids orally.
Conclusion
To conclude, cannabis is gaining popularity among patients who suffer from a wide variety of diseases. The plant contains phytocannabinoids analog of endocannabinoids in human organisms that are part of the endocannabinoid system. This system is responsible for reducing inflammation, and it explains the psychotropic effect of cannabis. Some people have impaired endocannabinoid systems, which is called endocannabinoid deficiency syndrome. Finally, to cure diseases, medical specialists use four routes of administration for cannabis, inhalation, oral, topical, and rectal, which have both advantages and disadvantages. Inhalation is a route with the fastest effect but is the most dangerous because of the combustion products. Oral administration allows for the safest dosing but is slower. Topical and rectal routes are the least explored, but they hold promises because they can act as local anti-inflammatory agents.
References
Bridgeman, M. B. & Abazia, D. T. (2017). Medicinal cannabis: History, pharmacology, and implications for the acute care setting. A Peer-Reviewed Journal for Managed Care and Hospital Formulary Management, 42(3), p. 180-188.
Bruni, N., Pepa, C. D., Oliaro-Bosso, S., Pessione, E., Gastaldi, D., & Dosio, F. (2018). Cannabinoid delivery systems for pain and inflammation treatment. Molecules, 23(10), p. 1- 25. doi:10.3390/molecules23102478.
Sallaberry, C. A., & Astern, L. (2018). The endocannabinoid system, our universal regulator. Journal of Young Investigators 34(6), p. 48-55. doi: 10.22186/jyi.34.5.48-55.
Sanchez, C. (n.d.). Routes of administration and cannabis products with therapeutic purposes. Fundacion Canna. Web.