Cannabis sativa (cannabis) is one of the oldest plants cultivated by men and it is one of the oldest psychotropic drugs known to humanity. There are several species of cannabis. According to archaeological discoveries, it has been known in China at least since the Neolithic period, around 4000 BC. Cannabis sativa and Cannabis indica have been used for centuries for a variety of medicinal and recreational purposes, but their routine use has been subject to societal and legal sanctions due to psychotropic and addictive effects.
Cannabis-based medicines are not new; tinctures of cannabis were available in several countries including the UK in the nineteenth century, and use continued until well into the twentieth century. There is growing evidence that cannabis-based medicines have potential for the treatment of a wide range of complex conditions, including symptomatic relief in multiple sclerosis, chronic neuropathic pain, intractable nausea and vomiting, loss of appetite and weight in the context of cancer or AIDS, as discussed by many scientists.
On the other hand, Cannabis unfortunately remains the most widely abused illicit drug around the globe. However, without analysing the important medicinal value of Cannabis and its pharmacological potential, use of cannabis in Sri Lanka is prohibited. Because it is considered as narcotic drug according to the Poisons, Opium, and Dangerous Drugs Act which states that “No person shall, without the licence of the Minister, sow, plant, cultivate, obtain, or have in his possession any Cannabis plant or collect or have in his possession the seeds, pods, leaves, flowers, or any part of any such plant.”
Cannabis sativa has been cultivated for more than 4500 years for different purposes. Its medicinal value was discovered in India as Ayurvedic medicine and cultivated as early as 900 BC. In India cultivation of this plant is controlled and permitted in several districts like Almora, Garhwal and Nainital (Uttarakhand, India) with small extent in Kashmir and Travancore.
Use of Cannabis has a long History
In Susruta, a renowned treatise on Hindu medicine possibly dating back to the 3rd to 8th centuries BCE, cannabis leaves are recommended for treating phlegm, catarrh (a build-up of mucus in the airways or cavities), diarrhoea, and biliary fever. Around the same period, Dwarakanath noted that cannabis was used in Indian folk medicine as an aphrodisiac and for pain relief. Numerous historical sources also describe cannabis as a general stimulant, known to enhance appetite, sharpen wit, and act as an aphrodisiac.
In 2019, an Indian study assessed the analgesic
potential of Cannabis sativa L. leaf powder in cancer patients with a poor
quality of life. The study found significant relief from cancer-induced pain,
anxiety, and depression. Notably, Cannabis sativa is also used in the
preparation of traditional Sri Lankan medicines.
Cannabis and its derivatives have been studied by major world bodies, including the UK House of Lords (1998), the US Institute of Medicine (1999), and Canada’s Senate (2002). Since 2003, medicinal cannabis has been available by prescription in the Netherlands. Several Western countries have authorized clinical trials, and since 1999, Canada has run a Medical Marihuana Research Program.
Chemistry of Cannabis
The Cannabis plant produces numerous bioactive compounds with potential medical benefits, including terpenes, flavonoids, and cannabinoids. Among these, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most extensively researched and studied compounds. Naturally occurring THC is the principal psychoactive compound. In humans, CBD exhibits no effects indicative of any abuse or dependence potential. However, there is no evidence linking recreational CBD use to health problems. CBD is known for health benefits, treating issues like stress, anxiety, sleep disorders, and chronic pain. Studies show that CBD has a therapeutic potential over a wide range of neuropsychiatric disorders. CBD has many diverse functions in the brain and there has been much interest in it as a pharmacotherapy for numerous disorders. Patients with Parkinson's disease (PD) have reported improvements in sleep and better quality of life with CBD. Studies in preclinical animal models and humans have provided evidence suggesting that CBD has neuroprotective, anti-inflammatory, anxiolytic, and antipsychotic properties. Further, it can be noted that, use of cannabis in Indigenous Medicine and in certain areas of Modern Medicine for a wide range of diseases and disorders is justifiably accepted.
CDB can be biochemically extracted and used for medicinal purposes. CDB in pure form can be exported to different countries to earn hard currencies sufficient enough to resolve all the financial problems prevailing in this country. This very idea was once proposed by the Author of this article in 2014 to the relevant authority in the Ministry of Health, but it was not materialized due to several reasons. In this context, it is sad to say that, Sri Lanka is still reluctant to explore this gold mine.
Cultivator and subsequent use of Medicinal cannabis
within the current legal system face a number of challenges. Consideration of Medicinal
Cannabis as a narcotic plant and its illegal abuse are major obstacles for
using it as a medicinal plant. There are several points to be considered in
elimination of abuse practices such as smoking and hence there should be a
concrete mechanism for adequate monitoring and prevention of addiction. Additional
research is also needed to validate drugs that will be produced as per
Traditional and Ayurveda drug recipes. Cannabis has immense potential as a
valuable commodity when cultivated and utilized with mindfulness, offering
economic, medicinal, and environmental benefits. However, its true value can
only be realized through responsible use, strong regulation, and public
education to prevent misuse.
University of Sri Jayewardenepura