Herbal cannabis to treat arthritis? Not recommended.

The suitability of using herbal cannabis to treat arthritis and related conditions is under scrutiny due to the results of a Canadian report.

A group of researchers looked at the dosing, administration, efficacy and risks of herbal cannabis in pain management in people with arthritis in the 20 US states where it is legal.

Publishing their results in Arthritis Care & Research, the team found that concentrations of tetrahydrocannabinol (the active substance in cannabis) vary in the plant material by up to 33%. Absorption rates fluctuate between 2% and 56%, so dosing of herbal cannabis is therefore unreliable.

No reliable data exists on the effectiveness of herbal cannabis in people with arthritis and similar conditions. And inhaling (ie smoking) herbal cannabis has adverse effects on the respiratory system from tar, hydrocarbons and carbon monoxide.

While some research has found that using cannabinoids can help cancer pain and neuropathic pain, the current study suggests this does not extend to arthritis conditions because they involve different pain pathways.

Added to the fact that long-term use of cannabis is associated with memory issues, mental illness and addiction, it seems fairly clear cut that using cannabis to manage arthritis pain is not a sensible option at the moment.

“At this time, we cannot recommend herbal cannabis for arthritis pain management given the lack of efficacy data, potential harm from the drug and availability of other therapies for managing pain,” says Dr Mary-Ann Fitzcharles, who led the work.