39 people underwent tests at the University of California, Davis Medical Center where experts conducted a double-blind, placebo-controlled, crossover study evaluating the pain reduction properties of vaporized cannabis.
Both the 1.29% and 3.53% vaporized THC study medications produced equal antinociception at every time point. … [T]he use of low doses could potentially be prescribed by physicians interested in helping patients use cannabis effectively while minimizing cognitive and psychological side effects. Viewed with this in mind, the present study adds to a growing body of literature supporting the use of cannabis for the treatment of neuropathic pain. It provides additional evidence of the efficacy of vaporized cannabis as well as establishes low-dose cannabis (1.29%) as having a favorable risk-benefit ratio.
The Department of Physical Medicine and Rehabilitation conducted this study and they are no strangers to cannabis research, back in 2009 they wrote another study that speaks of the poor marijuana research done until 2000 or so:
As recently as a decade ago a review of the world literature on the status of the efficacy and safety of cannabinoids for pain and spasticity revealed that only nine randomized studies of acceptable quality had been conducted. All of these were single dose studies comparing oral synthetic THC (or cannabinoid analogs or congeners) to codeine or placebo. … Authoritative reviews judged cannabinoids as being unlikely to have a role in acute pain management, but suggested there was enough evidence for efficacy in chronic neuropathic pain and muscle spasticity to warrant further research.
This lead their team of researchers to do more tests on neuropathic pain and other methods of medicating, like vaporizing and smoking. The recent study says vaporizing is the way to go:
… significant 30% reductions in pain intensity …
Folks, your doctor says get yourself a good vaporizer.