Reframing cannabis: a scientific overview | Maria Vella

The white paper ‘Towards the strengthening of the legal framework on the responsible use of cannabis’ as being proposed by the Maltese government sets out to debunk the myths and strip away the half-truths and noise in order to pave the way towards a regulatory legal framework on the use of cannabis in line with developments at EU level.

This regulatory legal framework is needed since cannabis – as is widely reported by scientists, social scientists, and economists, amongst other experts – has multiple positive medical and social attributes, yet a culture of fear remains due to lack of information. It has long been the most used and seized substance in Malta. As such, it is an issue that is here to stay and ignoring it is counterproductive on every level. The time has come to reframe the situation. A regulatory legal framework will help our society move forward with evidence-backed, transformative public policy.

For more than a thousand years, cannabis has been one of the most commonly used illicit drugs for both medicinal and recreational purposes. Its medicinal benefits have been widely acknowledged and documented. These include pain management, treatment of mood swings, anxiety and insomnia, and as an anti-inflammatory and anti-convulsant, amongst others. The research on the already-confirmed medical benefits of cannabis is still ongoing.

During the last century there has been a growing interest in cannabis since Prof. Raphael Mechoulam and his colleagues (1964) isolated and deciphered ∆9-Tetrahydrocannabinol (THC), the main psychoactive compound in the plant.

The cannabis plant has two main subspecies, Cannabis Indica and Cannabis Sativa, which can be differentiated by their physical characteristics. The Indica strains are short plants with broad, dark green leaves with higher amounts of cannabidiol compounds than that found in the Sativa strain, which in turn has a higher amount of THC compounds.

On the other hand, Sativa-dominant strains are taller plants with thin pale green leaves. It constitutes of an estimate of 426 chemical entities, 60 of which are cannabinoid compounds.

The roots and seeds do not contain any THC compounds, whilst materials from the dried stem typically contain 0.3% or less and the lower leaves less than 1% (Cannabis legislation in Europe, 2020). However, in female flowers and in plant hairs (the resinproducing trichomes), concentration of THC may reach up to 20% or more.

Cannabis potency is primarily evaluated according to a sample’s THC concentration.

This is the primary psychoactive cannabinoid in cannabis. The adverse effects after acute or regular cannabis use are in direct relation to THC concentrations in the product.

THC is the most known phytocannabinoid in the cannabis plant. Due to THC being the psychoactive compound in cannabis, it has been widely reported to be heavily involved with the body reward mechanism, resulting in a psychotropic high and possibly CUD (Cannabis Use Disorder) if unregulated (Pertwee et al., 2014; Barrie et al., 2017; Zehra et al., 2018; Kroon et al., 2019).

CBD is the second most prevalent phytocannabinoid in the cannabis plant. Differently from THC, CBD is a non-psychotropic phytocannabinoid, which at high dosages can modulate the intoxicating effects generated by THC (Jacobs et al., 2016). CBD is an antagonist of CBRs that can only interact indirectly to the latter receptors at high concentration.

Contrastingly to THC, CBD has been reported to bind to other non-CBR types of receptors albeit with low efficiency (Carrier et al., 2006; Cottone et al., 2013 & Pertwee et al., 2014).

As mentioned before, the contrast between the THC and CBD has also been highlighted as referred by the United Nations Conference for the Adoption of a Single Convention on Narcotic Drugs (1961).

Cannabis and cannabis resin were included in both Schedule I and Schedule IV of the 1961 Convention, putting cannabis in a specific category of hard drugs, such as heroin. However, in December 2020, they de-scheduled cannabis and its resin from Schedule IV and annotated the entry in Schedule I, wherein products with no more than 0.2% of THC are not under international control.

Maria Vella is chair of the cannabis technical committee