Smoked cannabis reduces chronic pain

August 30, 2010

For people suffering chronic pain, smoked cannabis reduces pain, improves mood and helps sleep, according to new research published in CMAJ (Canadian Medical Association Journal).

People who suffer from chronic neuropathic pain due to damage or dysfunction of the nervous system have few treatment options. These options include opioids, anticonvulsants, antidepressants and local anesthetics, but efficacy varies and all have side effects which limit compliance. Oral cannabinoids have shown success in treating some types of pain but may differ in effect and risks from smoked cannabis.

A team of researchers from McGill University Health Centre (MUHC) and McGill University conducted a to investigate the analgesic effect of inhaled cannabis in 21 participants 18 years and older with chronic neuropathic pain. The researchers used three different potencies of active drug (THC levels of 2.5%, 6% and 9.4%) as well as a 0% placebo.

Patients reported better sleep quality as the THC content increased. Anxiety and depression also decreased in the 9.4% THC group compared with the placebo group.

"We found that 25 mg herbal cannabis with 9.4% THC, administered as a single smoked inhalation three times daily for five days, significantly reduces average compared with a 0% THC cannabis placebo in adult subjects with chronic post traumatic/post surgical neuropathic pain," reports lead author Dr. Mark Ware, Director of Clinical Research at the Alan Edwards Pain Management Unit of the MUHC. "We found statistically significant improvements in measures of sleep quality and anxiety."

"To our knowledge, this is the first outpatient clinical trial of smoked cannabis ever reported," the authors state. It is one of only a handful of studies on smoked cannabis and neuropathic pain. The authors recommend more studies with higher potencies of THC, longer duration of follow-up and flexible dosing. Long-term safety studies of smoked cannabis for medical purposes are also needed.

In a related commentary, Dr. Henry McQuay of Balliol College, Oxford University, UK, writes "the authors should be congratulated for tackling such a worthwhile question as: does cannabis relieve neuropathic pain?, particularly because the trial must have been a major nightmare to get through the various regulatory hurdles. What makes it a worthwhile question is the continuing publicity that patients see, hear and read, suggesting analgesic activity of cannabis in neuropathic , and the paucity of robust evidence." He concludes that "this trial adds to the trickle of evidence that may help some of the patients who are struggling at present."

Explore further: Smokeless cannabis delivery device efficient and less toxic

More information: Research - www.cmaj.ca/cgi/doi/10.1503/cmaj.091414
Commentary - www.cmaj.ca/cgi/doi/10.1503/cmaj.100799

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ClickHere
5 / 5 (5) Aug 30, 2010
New research. Smoking pot reduces pain. Truly gound breaking.
yyz
5 / 5 (4) Aug 30, 2010
It's interesting to note that all cannabis in the study was administered by pipe. Many find pipes or cigarettes too harsh or irritating for repeated use and turn to devices like vaporizers to lessen these negative experiences. From the abstract: "The most common drug-related adverse events during the period when participants received 9.4% tetrahydrocannabinol were headache, dry eyes, burning sensation in areas of neuropathic pain, dizziness, numbness and cough."

Some of these side effects seem to be ameliorated through the use of vaporizers, so maybe future research might look more closely at this route of administration (and, of course, it can be eaten, but that's a different story altogether).
El_Nose
Aug 30, 2010
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