Specialist doctors registered with the General Medical Council (GMC) have been allowed to prescribe new medicines derived from cannabis since a policy change in November 2018. However, still research into these products has been limited creating an information vacuum about these medicines and their benefits or harms.
A new review authored by leading clinicians and scientists from the University of Bath and University College London (UCL) points to an array of different cannabis based products and cannabinoids available, and a strong need to educate both patients and clinicians into what these different products do and how they would help.
It points mainly to important differences between products containing THC (the main psychoactive and intoxicating constituent of cannabis) versus CBD (the non-intoxicating element). In certain medicines CBD and THC are combined for clinical benefit, while in others these components can work independently by playing different roles in improving certain symptoms.
For instance, several studies have found that a combination of CBD and THC can alleviate symptoms of chronic pain, while CBD alone can be effective for treatment-resistant epilepsy. By contrast THC alone can be effective for treating nausea and vomiting which is caused by chemotherapy. THC and CBD are both ‘cannabinoids’ which act in different ways on the body’s endogenous cannabinoid system.
The cannabis plant produces over 144 different cannabinoids which include THC or CBD. Some medicinal products do contain THC and/or CBD derived from the cannabis plant, whereas others contain synthetically produced cannabinoids. CBD is even available in non-medicinal products such as tinctures and oils.
Research on cannabis was earlier restricted because it was listed in Schedule 1, implying that it had no medical value, but it was recently moved to Schedule 2.