Australia needs to capture more data on product effectiveness and adverse reactions to medicinal cannabis, with prescribers key to compiling such information, researchers believe.
In a paper published in the International Journal of Environmental Research and Public Health, experts said the long term effects of cannabis remains unclear “and will continue to be poorly understood until signals of longer-term effects are detected”.
Writing in the journal, Dr Christine Hallinan and Yvonne Bonomo, both researches at the Australian Centre for Cannabinoid Clinical and Research Excellence, said the monitoring of the effects of medicinal cannabis has not kept pace with the rapid increase in the number of prescriptions.
The lack of analysis makes it hard to establish its effectiveness or detect side effects, they concluded.
The paper, The Rise and Rise of Medicinal Cannabis, what now? noted that a patient registry for the monitoring of medicinal cannabis effects and has not been established. Furthermore, while the TGA Database of Adverse Effects (DAEN) has received “adverse event notifications”, the number has been “minimal”.
“It has been established that the median time to detect adverse event signals from new therapies is 4.2 years for pharmaceuticals, and earlier when the introduction is fast-tracked,” the authors wrote. “We can therefore expect, especially considering the rapid rollout of medicinal cannabis, that there are signals that potentially remain undetected.”
Hallinan and Bonomo said doctors could fill the research gap, especially if monitoring is embedded into a GPs workflow via the GP electronic medical record (EMR).
“Since medicinal cannabis was legalised in Australia, there has been a rapid growth in prescribing in the community,” the paper concluded. “However, this expansion has not been accompanied by parallel processes for the monitoring of medicinal cannabis, which makes it difficult to establish its effectiveness in different conditions and difficult to detect side effects or adverse events.
“The capture of more highly granulated data, such as found in an established registry, would provide the opportunity to monitor product effectiveness and safety across indications and would be especially useful when incorporated with input from prescribers, practitioners, and consumers.”
The authors noted that other countries are increasingly engaging consumers through social media and apps in a move to better understand medicinal cannabis.
They added that evidence from published literature suggests adverse effects – including dizziness, sedation, confusion and diarrhoea – “appear to be manageable and short-lived”
However, they stressed the long-term effects will be poorly understood “until signals of longer-term effects are detected”.