By Pat Anson, PNN Editor

A study of the first patients prescribed medical cannabis after it was legalized in New Zealand in 2017 found that cannabidiol – the non-psychoactive ingredient in marijuana -- significantly improved their chronic pain and anxiety.

Researchers at the University of Auckland analyzed the health records of the first 397 patients prescribed cannabidiol (CBD oil) at a cannabis clinic in Auckland. The patients live with a variety of chronic pain conditions, including fibromyalgia, osteoarthritis, rheumatoid arthritis, neuropathy, multiple sclerosis, migraines and cancer.

Participants were asked to rate their pain, anxiety, mobility and depression before taking CBD oil and four weeks after starting treatment. The CBD doses ranged from 40mg/day to 300mg/day. The recommended daily dose was at least 100 mg.

Patients with non-cancer pain reported significant improvement in their pain, mobility, anxiety and depression. Some also said they slept better and their appetite improved.

Patients with neurological symptoms experienced no improvement with any symptom, and patients with cancer only reported improvement in pain.

Most patients said they were satisfied with CBD oil, with 70% reporting it was good, very good or excellent; while 30% reported no benefit.

Adverse side-effects, which included sedation and vivid dreams, were reported by about 10% of participants, with two patients (0.8 percent) reporting a worsening of a pre-existing condition.

“The study has limitations due to drop-out and other factors, but the findings are consistent with other evidence and underline the need for more research to allow us to fully realise the therapeutic potential of medical cannabis,” said Professor Bruce Arroll, senior author of the study and head of the Department of General Practice and Primary Healthcare at the University of Auckland.

“Our findings show that CBD is well-tolerated in most patients and can markedly ease symptoms in a range of hard-to-treat conditions, and that there are people keen to access this and self-fund the medication.”

Some patients chose not to take CBD oil because of its cost. Patients had to pay $300 (US) for 2500 mg of CBD oil, $150 for an initial consultation, and $75 for a follow-up.

“Our evidence of CBD’s potential benefits in treating pain and anxiety, if corroborated by future clinical trials, suggests we may need to consider subsidising medical cannabis,” said co-author Dr. Graham Gulbransen, who operates the cannabis clinic in Auckland. 

Because the study was observational and relied on patients self-reporting their symptoms, it did not establish a cause-and-effect relationship. It’s also possible the improvement in symptoms was due to a placebo effect.

The findings are published in the British Journal of General Practice Open (BJGP Open).