Swinburne University researchers have found medicinal cannabis may have minimal acute impact on cognitive function among patients with chronic health conditions.
In a semi-naturalistic, open-label trial, patients with various health conditions attended a single laboratory session in which they self-administered a standard dose of prescribed medicinal cannabis as per instructions on the pharmacy label.
The team assessed cognitive performance using the Cambridge Neuropsychological Test Automated Battery (CANTAB) and Druid application prior to and following self-administration.
Researchers also assessed subjective drug effects prior to and one, two and four hours after participants took their medication using a range of measures including ‘stoned’, ‘sedated’, ‘relaxed’, ‘comfortable’, ‘anxious’ and ‘confident’.
Of the 40 participants, 23 were prescribed oil while 17 vaporised flower. Chronic non-cancer pain was the most common indication, followed by sleep disorder and anxiety.
Participants’ performance improved over time on the CANTAB Multitasking Test and Rapid Visual Information Processing test. All other changes in cognitive performance measures were “non-significant”.
Meanwhile, vaporisation of flower was associated with significantly stronger subjective feelings of being ‘stoned’ and ‘sedated’ relative to oils.
Lead researcher Dr Thomas Arkell said the results could indicate that patients develop tolerance over time, “akin to what we see with other psychoactive medications like anti-depressants and benzodiazepines”.
He added: “It could also mean that patients experience some alleviation of their symptoms, such as pain, after using medical cannabis, which might lead to a normalisation of cognitive function.”
The findings were published in the journal CNS Drugs.
