Oral cannabis ineffective in treating acute pain

[Guest guest]

Oral cannabis ineffective in treating acute pain

http://www.news-medical.net/?id=39415

A study published in the July issue of the Journal Anesthesiology

discovered that oral cannabis (a form of medical marijuana) not only

failed to alleviate certain types of pain in human volunteers but,

surprisingly, it instead caused increased sensitivity to some forms

of pain.

In their research, Birgit Kraft, M.D., and her colleagues from the

Medical University of Vienna evaluated the analgesic potency of

orally administered cannabis extract that included its main

psychoactive component, Tetrahydrocannabinol (THC).

" The surprising result of our study was the absence of any kind of

analgesic activity of THC-standardized cannabis extract on

experimentally induced pain using well-established human model

procedures, " said Dr. Kraft. " Our results also seem to support the

impression that high doses of cannabinoids may even cause increased

sensitivity in certain pain conditions. "

In Dr. Kraft's study, 18 healthy female volunteers were given oral

cannabis extract or active placebo and then evaluated for heat and

electrical pain thresholds in skin areas of experimentally induced

sun burn, an accepted approach to assessing responses to acute pain.

Previous studies have suggested that cannabis and THC may be

effective in treating chronic pain, such as in cancer patients,

patients with spinal cord injury, or those with multiple sclerosis.

And, though inconsistent, some studies on patients with acute pain

have suggested beneficial effects

Consistent with the uncertainty about oral cannabis ingestion

evaluated in this study, there is also uncertainty in the research

community as to whether inhaled cannabis might prove more efficacious

for pain relief than orally ingested cannabis.

Dr. Kraft's results concerning oral cannabis for acute pain were

seemingly conclusive. " From comparisons with previous clinical data,

the lack of pain relief from the cannabis dosage and oral

administration in our study cannot be considered the result of

inadequate dosage or insufficient gastrointestinal absorption, " said

Dr. Kraft. " The high levels of THC detected in the blood of our

subjects as well as the occurrence of typical THC side effects argue

for sufficient availability, and thus we draw the conclusion that THC

was not effective in treating acute pain. "

Dr. Kraft stressed, however, that cannabis may still remain a viable

option for certain types of chronic pain patients.

" Pain is a very complex and subjective phenomena, " she said. " Chronic

pain has not only been shown to lead to changes in peripheral and

central neuronal processing, but also to be associated with

psychosocial problems, physical disorders, and functional

disabilities. Recent studies have indicated that cannabis can be

effective in treating certain types of chronic pain and helping

patients to cope by improving quality of life. "

Dr. Kraft and her colleagues concluded that contemporary treatment

strategies that rely on experimentally proven therapies still remain

the best option for most patients suffering acute pain.

" In patients with acute pain, other analgesic drugs such as narcotics

and non-steroidal anti-inflammatory drugs (NSAIDs) produce more

reliable and potent analgesia, " she said.