Known from antiquity for its analgesic properties cannabis was introduced to Western medicine in 1838 by William B. O'Shaughnessy who described significant improvement in a case of severe chronic arthritis. Clendinning in 1843 reported significant pain relief and compared cannabis favorably with opiates. Throughout the 19th century it was extensively used in a variety of painful conditions. Unavailable to the clinician until 1985 with the release of synthetic delta 9 tetrahydrocannabinol as a schedule II controlled substance, its labeled and approved indications were limited to nausea and side effects of cancer chemotherapy. California permits off label usage and clinical experience has shown that dronabinol (Marinol)(delta 9 THC) to be efficacious in some cases. Crude cannabis was noted to be efficacious in pain management by some 8,000 self-medicators interviewed by the author when they were evaluated for eligibility under the California Compassionate Use Act of 1996. The salient feature of cannabis was absence of unwanted side effects of opioids, sedatives, and non steroidal anti inflammatory drugs. For chronic pain management these undesirable effects become problems themselves. Cannabis also produces elevation of mood and normalization of vegetative functioning. Emotional modulative effects of cannabis significantly enhance pain management. Route of administration and circadian timing are critical for appropriate and desired clinical result. Recent application of a phenomenon discovered in the 5th century B.C. by the Scythians: vaporizing cannabis by heat extraction of the essential oils without burning - avoiding medical and social irritation . Sublingual cannabis pharmaceuticals developed by GW Pharmaceuticals will be marketed in 2004 by Bayer for chronic pain management in Great Britain, Europe, and Canada.
© 2004 Published by Elsevier Inc.