The demand for medicinal cannabis has exponentially increased in the last few years with claims that cannabis is an extremely effective medication for treating a multitude of different conditions including chronic pain, anxiety, epilepsy, arthritis and multiple sclerosis. Medicinal cannabis was legalised in the UK on the 1st November 20181, however, it has been reported that an extremely low number of prescriptions have been issued since. This leaves people paying high prices for private prescriptions or facing fear of prosecution if sourcing it illegally. A survey carried out by the Centre for Medicinal Cannabis (CMC) and the Cannabis Advocacy and Support Services (CPASS) reported that approximately 1.4 million people in the UK source cannabis illegally for treatment of different medical issues2. These figures reveal a large population experiencing health conditions which cannabis could treat and a potential issue with the restricted prescriptions of CBD based medicines.
Cannabidiol (CBD) and Tetrahydrocannabinol (THC), the two most familiar compounds associated with cannabis, can be found within many licenced medical products. The mechanism of action of these compounds are not fully understood, however, through clinical research, CBD has demonstrated analgesic, anticonvulsant, anti-inflammatory and anxiolytic properties. It is known that both THC and CBD work by interacting with the receptors of the endocannabinoid system in our bodies. THC binds to and activates the CB-1 receptors, which are found in the brain and this interaction produces the euphoria associated with being “high”. Conversely, CBD has been proven to be an antagonist of CB-1 receptors, meaning it binds to them and prevents their activation3,4. There is evidence that CBD can inhibit the breakdown of endocannabinoids, allowing the effects to be felt for a longer period of time. For example, anandamide, an endocannabinoid that binds to the CB-1 receptor during the ascending pain pathway, dampens the feeling of pain. Taking CBD is reported to have analgesic effects which could be attributed to the fact that it decelerates the degradation of anandamide from the CB-1 receptor5.
Addiction is becoming an increasingly worrying problem around the world with more people becoming dependent on opioids such as fentanyl. The National Academies of Science and Medicine has reported that using medicinal cannabis decreased opioid use by 64% in patients with chronic pain6. There is potential for CBD to be used as a treatment for addiction around the world, however, there is a possibility of this leading to cannabis addiction. Cannabis accounts for an estimated 25% of total drug addiction around the world7 thus, protocols should be put in place so that medication is regulated, and regular check-ups with a healthcare professional are maintained.
Recently, the NHS have approved two cannabis-based medications for routine use in the UK. Epidyolex has been fully licensed for the treatment of two forms of severe epilepsy, Lennox-Gastaut syndrome or Dravet syndrome which are mainly found in children and cause serious seizures. With Lennox-Gastaut syndrome accounting for approximately 5-10%8 of all epileptic patients, Epidyolex has the potential to help a lot of people. The drug contains CBD which can help to prevent these seizures, possibly by targeting the movement of ions into cells, which impacts the transmission of electrical signals around the body9. Sativex, the other recently approved drug, aims to relieve symptoms of multiple sclerosis, including severe muscle spasms, pain and bladder issues10.
More research is required to determine the efficacy of medicinal cannabis products and to ensure people have access to safe and regulated treatments in order to improve their quality of life.
1. GOV.UK (2018) Government announces that medicinal cannabis is legal [Online]. Available at: https://www.gov.uk/government/news/government-announces-that-medicinal-cannabis-is-legal [Accessed: 15/11/19]
2. The Centre for Medicinal Cannabis (2019) ‘New poll reveals 1.4 million British adults using ‘street cannabis’ to treat chronic health conditions’ [Online] Available at: https://pressat.co.uk/releases/new-poll-reveals-14-million-british-adults-using-street-cannabis-to-treat-chronic-health-conditions-7ddc0e8040bbefc376303825fdd476e7/ [Accessed: 15/11/19]
3. DRUGBANK. (2019) Cannabidiol. [Online]. Available at: https://www.drugbank.ca/drugs/DB09061 [Accessed: 15/11/19]
4. Laprairie RB et al (2015) ‘Cannabidiol is a negative allosteric modulator of the cannabinoid CB1 receptor’, British Journal of Pharmacology, 172, p4790-4805
5. Leweke FM et al (2012) ‘Cannabidiol enhances anandamide signalling and alleviates psychotic symptoms of schizophrenia’, Translational Psychiatry,2(94),p1-7
6. Boehnke KF et al (2016) ‘Medical Cannabis Use Is Associated with Decreased Opiate Medication Use in a Retrospective Cross-Sectional Survey of Patients with Chronic Pain’, The Journal of Pain, 17(6), p739-744
7. Ritchie H et al (2018) ‘Drug Use: Prevalence of Drug Use Disorders’, Our World in Data [Online]. Available at: https://ourworldindata.org/drug-use [Accessed: 15/11/19]
8. Orphanet  Lennox-Gastaut Syndrome: Summary [Online]. Available at: https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=2382 [Accessed: 18/11/19]
9. European Medicines Agency. (2019) Epidyolex (cannabidiol) [Online]. Available at: https://www.ema.europa.eu/en/documents/overview/epidyolex-epar-medicine-overview_en.pdf [Accessed: 15/11/19]
10. MS Society (2019) Sativex [Online]. Available at: https://www.mssociety.org.uk/about-ms/treatments-and-therapies/cannabis/sativex [Accessed: 15/11/19]