The long-term, daily use of cannabis is associated with improved analgesia and reduced opioid use in patients with treatment-resistant chronic pain conditions, according to clinical trial data reported online ahead of print in The Clinical Journal of Pain.

Investigators with Hebrew University in Israel evaluated the use of cannabis on pain in a cohort of 176 patients, each of whom had been previously unresponsive to all conventional pain medications. Subjects inhaled THC-dominant cannabis daily (up to 20 grams per month) for a period of at least six months.

A majority of participants (66 percent) experienced improvement in their pain symptom scores after cannabis therapy, and most reported robust improvements in their quality of life. Subjects' overall consumption of opioid drugs declined 44 percent by the end of the trial, and a significant percentage of participants discontinued opioid therapy altogether over the course of the study.

Authors concluded, In summary, this long-term prospective cohort suggests that cannabis treatment in a mixed group of patients with treatment-resistant chronic pain may result in improved pain, sleep and quality of life outcomes, as well as reduced opioid use.

The Israeli results are similar to those reported in a 2015 Canadian trial which concluded that chronic pain patients who use herbal cannabis daily for one-year experienced reduced discomfort and increased quality of life compared to controls, and did not possess an increased risk of serious side effects.

According to data published in 2014 in The Journal of the American Medical Association, US states with medical marijuana laws experience far fewer opiate-related deaths than do states that prohibit the plant. Investigators from the RAND Corporation and the University of California, Irvine reported similar findings in 2015, concluding, States permitting medical marijuana dispensaries experience a relative decrease in both opioid addictions and opioid overdose deaths compared to states that do not. Clinical data published in 2011 in the journal Clinical Pharmacology & Therapeutics previously reported that the administration of vaporized cannabis safely augments the analgesic effect of opioids.

A review published earlier this year in the Canadian Journal of Anesthesia assessing the clinical use of cannabinoids for pain in over 1,300 subjects concludes, Overall, the recent literature supports the idea that currently available cannabinoids are modestly effective analgesics that provide a safe, reasonable therapeutic option for managing chronic non-cancer-related pain and possibly cancer-related pain.

Source: http://blog.norml.org/2016/02/22/study-long-term-cannabis-use-associated-with-improved-pain-relief-reduced-opioid-use