Cannabis is a plant with therapeutic activity that has not yet been fully explored. Its clinical contribution to pain, nausea, and sleep disturbance has been proven. There are indications of its potential utility in treating other diseases and disorders, but without full clinical proof (Bar-Lev Schleider et al. 2018). Some active substances from cannabis (cannabinoids) or synthetic cannabinoids have been approved for use as active pharmaceutical ingredients (API) by the Food and Drug Administration (FDA) and other authorities. Examples of these approved substances include dronabinol, nabilone, and nabiximols (Sativex) (Haney et al. 2013; Kluger et al. 2015; Abuhasira et al. 2018).

In past years, cannabis was universally subject to prohibition in most countries (UN 1961; Papaseit et al. 2018). However, the current landscape presents a stark contrast, with cannabis now standing as the most commonly consumed illicit drug in Europe. In 2022, it was estimated that approximately 8% of European adults between the ages of 15 and 64 years had engaged in cannabis use, representing 22.6 million individuals. Furthermore, an estimated 1.3% of European adults (3.7 million people) are considered daily or near-daily users of cannabis (European Monitoring Centre for Drugs and Drug Addiction 2023a). Herbal cannabis is the most commonly available form for use. It is utilized by 95% of cannabis users, compared to 32% for resin, 25% for edibles, and 17% for extracts (European Monitoring Centre for Drugs and Drug Addiction 2023a). A noteworthy shift has occurred since the early 1990s when the primary form of cannabis used in Europe was cannabis resin imported from external sources. The increased prevalence of herbal preparations is linked to the replacement of imported resin with domestically cultivated herbal cannabis of European origin. Resin, in contrast, represents a more industrialized product, while herbal cannabis, given its natural origin, exhibits greater diversity in its inherent qualities (European Monitoring Centre for Drugs and Drug Addiction 2012).

The high use of illicit cannabis and the knowledge about its medical contribution confront countries deciding on its clinical and legal status. Previous research has often viewed cannabis medicalization and legalization as closely linked processes (Pacula and Smart 2017; Hall 2020), but it is important to emphasize that these two statuses are distinct: the clinical status refers to medical cannabis (mainly herbal cannabis), while the legal status relates to recreational cannabis use. This distinction allows for a more nuanced understanding of cannabis policy development in Europe.

Not all health systems recognize the medical potential of cannabis; indeed, some actively oppose or ignore it. Bulgaria and Romania are examples of such opposition (Abuhasira et al. 2018). If the medical value of cannabis is acknowledged, there is more than one clinical policy to follow. A possible clinical policy for cannabis is pharmaceuticalization (Williams et al. 2011; Cloatre and Pickersgill 2014; Sismondo 2015). In pharmaceuticalization, the focus is primarily on harnessing the therapeutic effects of cannabis without considering the entire herbal cannabis plant as a medical product. In this policy, cannabis, like other narcotic drugs, is considered dangerous but with some medicinal value. The Convention on Psychotropic Substances (UN 1971) classifies THC, one of the cannabinoids, as “use is prohibited except for scientific or limited medical purposes”.

In pharmaceuticalization, it is only possible to use cannabinoids and develop medicines based on them (like using Botulinum toxin from Clostridium botulinum bacterium to manufacture commercial formulations for cosmetic applications). An additional option is to synthesize cannabinoid-like substances chemically. This policy primarily involves pharmaceutical companies as the key stakeholders, with minimal involvement from regulatory authorities and little to no participation from sectors such as cannabis cultivation. For example, France and Iceland have chosen this policy (Abuhasira et al. 2018). Cannabinoids-based pharmaceuticals can be approved by a centralized EU framework (based on Directive 2001/83/EC) or by European countries (Lipnik-Štangelj and Razinger 2020).

Another clinical policy is medicalization. Medicalization, among others, is the integration of new practices or interventions into medicine. For example, when the official health system integrates complementary and alternative medicine (Shuval et al. 2012; Sismondo 2015; 2020; Zarhin 2020). Within the framework of medicalization, the herbal cannabis plant is formally recognized as a pharmaceutical product possessing medicinal attributes. In this policy, multiple stakeholders are involved: regulatory authorities establish standards for cannabis products and growing conditions, offer guidance and training to medical practitioners, and allow the distribution of user licenses to patients; cultivators grow the cannabis according to the standards; service labs test the produce; physicians closely monitor the patients who consume medical cannabis documenting both its clinical effectiveness and any observed side effects, which is then reported to regulatory authorities; research centers are researching the cannabis and his effects advancing our understanding of the subject; and finally, regulatory authorities, equipped with insights from these various stakeholders, continually refine cultivation requirements and medical guidelines for healthcare professionals (Zarhin et al. 2017; Israeli Medical Cannabis Agency at the Ministry of Health 2019; Zarhin 2020).

Within the medicalization policy, THC content in herbal cannabis can be regulated, while in non-regulated herbal cannabis, the THC content varies considerably (European Monitoring Centre for Drugs and Drug Addiction 2023a). Countries that have embraced this policy include Germany, Israel, and Italy (Abuhasira et al. 2018). Herbal cannabis, magistral preparations, and other forms of herbal cannabis (e.g., cannabis oil extracts) are not approved by the EU framework (Directive 2001/83/EC), only by national pharmacopeia or other national schemes (Lipnik-Štangelj and Razinger 2020). To summarize, we identify three clinical policies that differ in the attitude toward cannabis plants and their utilization, as outlined in Table 1. In particular, Table 1 can help to draw the distinction between medicalization and pharmaceuticalization.

In the legal governance, countries employ a range of models to address recreational cannabis use. These models are different regarding the use of cannabis (personal use or for sale, use by adults or use by teenagers, self-cultivation or distribution), the criminal sanctions, the levels of law enforcement (de jure or de facto), and other distinctions (Room et al. 2010). However, despite these divergences, these legal paradigms can be broadly categorized into three primary regime types: prohibition, decriminalization, and legalization (Room et al. 2010; Fischer et al. 2020). Prohibition characterizes a regime where cannabis use is prohibited and subject to criminal sanctions. Decriminalization describes a regime where cannabis use is prohibited yet controlled by civil penalties. A legal regime that entirely removes all punitive sanctions from cannabis use (de jure or de facto) is referred to as legalization (Room et al. 2010).

Legalizing cannabis has several benefits, including decreases in cannabis-related crimes, decreasing law enforcement and judicial costs, a reduction in synthetic cannabis supply, a decline in underground economies, and a potential decrease in illegal drug transactions. However, it is crucial to address the reported problems associated with legalization, such as increases in cannabis use, cannabis-related disorders, and cannabis-related accidents and hospitalizations (Cabral Barata et al. 2022). While numerous European countries decriminalized the recreational use of cannabis, it is still illegal in most European countries.

Another way to assess the legal scope for recreational cannabis use is by checking the penalty level in the law for the consumption of cannabis. Some European countries have a prison as the maximum penalty, some have a fine or other minor penalty, and others have no penalty at all (European Monitoring Centre for Drugs and Drug Addiction 2023b). The European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) categorizes penalties into three levels. The first level is incarceration (prison), the second is a penalty without incarceration, and the third imposes no penalty (European Monitoring Centre for Drugs and Drug Addiction 2023b).

This research aims to explain the correlation between the clinical policy of herbal medical cannabis and the legal regime of recreational cannabis, focusing on European countries.