Medicinal cannabis : issues of evidence

Introduction: Medicinal cannabis has been used for over 6000 years. It may be accessed legally in many western countries, yet in Australia, access is very difficult. It is treated as a pharmaceutical and an ‘unapproved therapeutic good’, and is subsequently subject to a complex regulatory system around prescribing. There have been calls by authoritative bodies in Australia for more evidence in relation to its efficacy and safety, suggesting that this is inadequate. The adoption of the evidence-based medicine (EBM) approach as the basis of decision-making in the healthcare sector positions systematic reviews and randomised controlled trials (RCTs) at the top of the hierarchy of evidence. It is largely this form of evidence that has been used to argue for or against the efficacy and safety of cannabis and to substantiate the current regulatory system in Australia. It is therefore important to understand the EBM approach and factors that need to be considered when examining scientific research into cannabis, in order to decide whether there is sufficient evidence or not. It is argued that regulation of cannabis is inappropriate, based on a limited understanding of evidence, and continues to limit access to medicinal cannabis by patients. Methods: This paper examines the notion of evidence in medicine, points of consideration in scrutinizing research methodology, what the actual evidence is in relation to safety and efficacy of medicinal cannabis, the implications of evidence and whether it supports the current regulatory framework around medicinal cannabis in Australia. It poses an alternative regulatory approach. Results: A robust definition of EBM goes beyond the notion of simply scientific evidence in the form of RCTs and systematic reviews. Rigorous scrutiny of the evidence about cannabis is required, since evidence is being used to control access. Scientific evidence including reports from authoritative bodies indicates there is much evidence to support the safety and efficacy of medicinal cannabis. CBD has been found to be relatively safe, non-addictive and efficacious. Access to medicines that alleviate suffering in a timely manner is a human right and a medical responsibility. There is enough evidence to justify regulatory changes to significantly increase access to medicinal cannabis in Australia. Conclusion: We need to bring back the human element when considering what evidence we use and how we use it in medicine. Cannabis has the potential to alleviate much suffering, and patient (human) rights must be central in public policy. There is already much scientific evidence in relation to safety and efficacy of cannabis and cannabinoids such as CBD and THC. In Australia, the current regulatory system needs to be disbanded, cannabis products treated as ‘approved goods’ and regulated as complementary medicines (for products containing CBD and low THC) or in the case of high THC-containing products, regulated under the SUSMP as an S4 (rather than S8) medicine.