We conducted an all-Ireland survey to determine the views and perspectives of Irish neurologists regarding the use of cannabis-based medicines in their practice. Data presented herein indicate that neurologists have an average knowledge of cannabinoid-based medicines, acquired predominantly from colleagues. In addition, our findings indicate that the majority of neurologists surveyed are aware of systems to access cannabis-based products for medicinal use in Ireland, and that approximately one-third of neurologists that completed the study have made applications to the MCAP and(or) Ministerial licence scheme to access cannabis-based medications on behalf of their patient(s). Importantly, this study indicates that educational programmes on the cannabinoid system and cannabis-based medicines are warranted.

The findings of the study indicate that consultant neurologists had a significantly greater score than non-consultant trainee neurologists in terms of the opinion of their knowledge of cannabis-based medicines. This difference in knowledge is likely due to a higher level of clinical experience amongst consultants and greater front-line exposure to more complex clinical cases. In addition, a factor in this regard may be that prescription of cannabis-based medicines is restricted to consultant use only, resulting in a lack of real-world experience for non-consultant hospital doctors. In support of this, our findings indicate that consultants, when compared to trainees, reported an increased awareness of both the MCAP (83% versus 63%) and Ministerial licence scheme (72% versus 31%). The majority (77%) of survey participant’s reported that their knowledge ranged from average to excellent. Clinical guidelines for the medical use of cannabis have been available in Ireland via Government sources since 2020 [12], and the availability of such guidelines may reflect such data. This is somewhat in contrast to findings elsewhere reporting physicians’ experiences and attitudes towards medical cannabis. Indeed, data from Rønne et al. (2021) report that clinicians generally experience a lack of knowledge regarding the clinical effects of medical cannabis, including beneficial and adverse effects [25].

The current regulatory framework surrounding the use and access of cannabis-based medicinal products in Ireland is complex. Our findings indicate that approximately one-third of neurologists included in the study have made an application to the medical cannabis access programme on behalf of a patient. This is consistent with data indicating a perceived lack of evidence-based knowledge amongst clinicians [25]. It is likely that the complexity of regulatory framework in Ireland presents an obstacle to the engagement of clinicians in the access programmes. This may be further compounded by the number of different formulations available and the lack of clarity regarding drug doses. Indeed, authorised cannabis-based medicines in Ireland, and products accessed via the Ministerial licence scheme and MCAP, include products that are administered via oromucosal spray, oils, tablets and via inhalation [14]. With significant and continued policy changes on a country-by-country basis, there is similar regulatory complexity in a European context [26]. Indeed, regulations governing access to cannabis products vary by country [27]. In general, cannabinoid-based medicines, particularly Sativex®, Cesamet® and Marinol®, are authorised in several countries in Europe [26, 28]. As an example, a recent German study indicates that Sativex® is authorised in Germany for the management of spasticity in MS, while Cesamet® is authorised on prescription for chemotherapy-associated nausea and emesis. Marinol® is also available for no-label use in Germany [29]. As a further example, in the UK, cannabis-based medicinal products were re-scheduled by the Home Office in 2018, which facilitated a pathway to prescribing cannabis-based medicines by consultant physicians when conventional treatments have not met treatment targets [30]. Approximately 32,000 patients had received prescriptions for cannabis-based medicinal products in the UK by the end of 2022, predominantly for chronic pain, anxiety and fibromyalgia [31, 32]. Twelve percent of our study cohort was based in the UK, and although our study is statistically underpowered to stratify our findings based on practice location, it is likely that regulatory differences based on geographical location may impact prescription numbers to patients in Ireland.

Our research examined the sources of information utilised by neurologists to learn about cannabinoid-based medicines. We found that “colleagues” emerged as the most common source of information. This is in contrast to data elsewhere indicating that neurologists predominantly access medical literature to formulate their opinions and beliefs regarding cannabis [20, 22]. Indeed, just one neurologist (a trainee) in our study indicated that they access peer-reviewed publications to access information on access programmes. However, it is noteworthy that the use of cannabis and its derivatives for therapeutic purposes is an emerging topic in modern medicine, and it is reasonable to suggest that there may be a lack of peer-reviewed research literature in the context of the Irish healthcare system. Furthermore, study participants indicated that they obtained information from secondary sources, such as websites. Web sources were the next most common source of information by which neurologists accessed information on medicinal cannabis access programmes. This suggests that there is a gap in knowledge amongst neurologists in Ireland regarding cannabinoid-based medicines, and this is supported by 10-point Likert scores (10 = strongly agree and 1 = strongly disagree) regarding the question “Educational programmes on the cannabinoid system and cannabis-based medicines are required” (mean Likert, 8.53; Table 3). Open-ended responses included statements such as “This area needs more awareness among clinicians” and “medical schools do not teach about cannabis dosing/side effects etc. then suddenly we are being asked to prescribe and take responsibility for it with no teaching/training”.

Our findings regarding the need for formal professional training and educational programmes on cannabis and cannabis-based therapeutics for clinicians are supported by data from many studies elsewhere in jurisdictions such as Canada, USA, Israel and Norway [16, 17, 20,21,22, 33,34,35,36]. Indeed, data indicate a need for education to inform clinicians on safety issues [21], with findings from our study and elsewhere indicating that training about medicinal cannabis should be incorporated into medical school curricula [20, 35]. As far as we are aware, there is an absence of formal educational and training programmes on the endocannabinoid system, and cannabis-based medicines, in the Irish healthcare system, and this is likely to impact engagement with access programmes and the number of prescriptions given for medicinal cannabinoid products in Ireland.

Data presented herein indicate that there is a general consensus amongst neurologists that there is sufficient evidence base to support the use of cannabinoid-based medicines for symptom management in certain conditions and that overall, neurologists are interested in the use of cannabinoid medicines in medical practice. This is consistent with studies in other clinical cohorts indicating that the majority of study participants are supportive of incorporating the use of cannabinoids into clinical practice for treatment/symptom management in certain conditions [33, 34, 36]. In Ireland, consultants play a key role in access to cannabis-based medicinal products, and specifically, neurologists are often the patients’ first contact point in the healthcare system to coordinate their treatment given that MS-associated spasticity and severe, treatment-resistant epilepsy are indications recommended under the HPRA review of medical cannabis [13].

The views of study participants regarding the appropriateness of the access programmes to prescribe cannabis-based products were mixed, suggesting that the study cohort is uncertain about navigating the current systems in place. Feedback reported in Table 4 included “Not enough knowledge of the system to answer” and “Not fully abreast of the process to comment”. The regulatory and legal frameworks in Ireland regarding the use and access to cannabis-based medicinal products in Ireland are complex, with the existence of regulatory hurdles and potential uncertainty regarding clinical guidelines. In other jurisdictions, systems are in place to monitor safety and outcomes when prescribing cannabis-based products [37]. It is reasonable to suggest that the development of a national monitoring system (to monitor safety, side effects, adverse events, positive outcomes) may alter the views of clinicians in Ireland regarding the appropriateness of the MCAP and Ministerial licence scheme.

Importantly, at the end of the survey, neurologists completed open-ended responses. Quotations from the study participants are presented in Table 8, with feedback indicating “I think it would be beneficial if a senior SpR/Fellow could also prescribe to take burden of workload off consultants”. This suggests that time constraints, in terms of processing applications to fill prescriptions, may be an important consideration and suggests that a more streamlined process may negate delays in the process and improve engagement.

The main limitation of this study is the low sample size, although the response rate was in line with studies elsewhere [16, 21, 22, 33]. It is noteworthy that the number of neurologists that completed the study in full reflects the limited size of the Irish neurologist community. The study participants may have been motivated to complete the study based on strong opinions on cannabis use per se, and the prescription of cannabis-based medicines. In addition, the study does not capture the perspectives of other consultants and healthcare providers (e.g. nurse practitioners). This was beyond the scope of the current study and will be the focus of future studies from our group. Finally, neurologists completed open-ended responses to allow study participants to give further views on the study, with quotations from the study participants presented in Table 8. Feedback indicated “why you haven’t asked regarding how one is finding it working in your patients”. Such responses regarding patient feedback views and perspectives on cannabis-based medicines in Ireland will also be a focus of future studies. Despite this, the current study is the first all-Ireland study to determine the perspectives of neurologists on cannabis-based medicines.