A new study confirms that vaporization, which involves heating marijuana to release cannabinoids without burning it, "is a safe and effective mode of delivery of THC." California researchers randomly assigned 18 healthy subjects to inhale vapor from a Volcano brand vaporizer loaded with marijuana of different potencies (1.7, 3.4, and 6.8 percent THC). As expected, the subjects inhaled less vapor from the stronger pot, more from the weaker pot, achieving similar THC blood levels regardless of the cannabis they received. NORML News reports that the subjects absorbed, on average, 54 percent of the released THC, compared to the 20 percent or so typical of smokers, while avoiding the toxins generated by combustion. Health and comfort considerations aside, this marijuana-conserving difference could easily justify the investment in a vaporizer for regular users. The Volcano retails for $540 or so, and there are cheaper competing products, although I don't think Consumer Reports has gotten around to rating them.
In short, vaporization is an appealing alternative for patients (or recreational users) who want the quick action and dose control of smoking without the smoke. Oddly, this option was overlooked in the 1999 National Academy of Sciences report on medical marijuana that called for the development of smoke-free cannabinoid delivery methods, although vaporizers were commercially available at the time. And no, I don't own any stock in Storz & Bickel, the Volcano's manufacturer, although I wish I did.