An overview of global monitoring systems for the side effects and adverse events associated with medicinal cannabis use: A scoping review using a systematic approach
Authors: Wang Rebecca Qi , Bonomo Yvonne Ann , Hallinan Christine Mary 
Published: February 2024

The use of cannabis-based medicines (CBM) as a therapeutic has grown exponentially over the last 5 years in Australia. Prior to this increase, there was significant legislative resistance to the use of CBM for clinical trials, hence pre-clinical data is limited. Safety monitoring systems for CBM are not structured and do not fit easily into the workflow of busy health professionals. Hence, post-marketing surveillance of CBM is patchy. CBM are available in many countries globally and face similar issues in relation to pharmacovigilance. The objective of this review is to answer the following question: What are the systems in place internationally to monitor side effects and adverse events of cannabis use as a medicine?

We used the PICO framework to develop keyword elements, which guided two search queries. Each query contained a different combination of keywords to increase sensitivity and specificity of the search. Both queries were entered into Embase and Scopus for retrieval of quality relevant peer-reviewed literature. Only the second search query, was used for the grey literature. Fifty-four full text articles were included in the review, thirty-nine were from the peer-reviewed search, eight were from the grey literature search, and seven were from citations of relevant texts.

Our search yielded two main forms of monitoring systems: databases and registries, with databases often created by regulatory authorities. There was great variability within these systems, differing in methods of causality assessment, level of detail collected, terminology, and affiliations. Only one monitoring system captured in our search obligated reporting from patients.

VigiBase remains the largest form of centralised monitoring, receiving case reports internationally. Regardless of the scope of VigiBase, there remains heterogeneity of data within the system. As such, our study reaffirms a greater need for a centralised, consistent, and accessible system for the post-marketing surveillance of side effects and adverse events associated with usage of CBM.

KEY MESSAGES

What is already known on this topic

Real-world data is essential for monitoring the side effects and adverse events associated with the use of cannabis-based medicines, given the limited availability of clinical trials, increasing clinical demand, and rising accessibility to unregulated cannabis-based products.

In some countries, registries and databases exist for post-marketing surveillance of side effects and adverse events at a national level.

What this review adds

A summary of the current landscape of monitoring systems at an international level, and interactions, and reporting hierarchies that exist between systems.

An analysis of the content, specificity, and scope of each monitoring system, including an analysis of the reporting type, be it mandatory or spontaneous.

How this study might affect research, practice, or policy (summarise implications)

A robust and standardised system is required for ongoing post-marketing surveillance of the side effects and adverse events associated with usage of cannabis-based medicine.

Development of a system that is both accessible and well-integrated into healthcare professional clinical workflow is needed.

Future practice and policy guided by this research can establish a standardised approach for collecting safety data that aligns with the rapid adoption of cannabis-based medicines in clinical settings.