A new study conducted from June 2016 to January 2017 at the Johns Hopkins University of Medicine Behavioral Pharmacology Research Center in Baltimore administered doses of 0mg (placebo), 10mg and 25mg of vaporized (via a Volcano vaporizer from Storz and Bickel) and provided cannabis to participants to study the differences of effects between the two modes of administration and as a function of dosage. The study concluded that there was a significant difference in the effects between vaporized cannabis and smoked cannabis.

The study assessed the effects of cannabis in subjective terms and by performing cognitive and psychomotor performance tests. She also monitored cardiovascular vital signs and THC levels in the blood. The observed sample consisted of 17 healthy adults, nine male, and eight female, who were not regular cannabis users and had not used cannabis in the 30 days preceding the tests.

The results of the study

Cannabis use has had significantly different results depending on whether it is smoked or vaporized. This may be due in part to the fact that combustion destroys some of the cannabinoids. At 10mg and on a scale of 1 to 100 the effects of cannabis were estimated at 46 by smoke and 69 by vaporization. However, cognitive effects remain moderate in both cases. With the 25 mg dose, the difference is reduced with 66 smoked and 78 vaporized, but the reduction in cognitive and psychomotor abilities is more visible, with less performance compared to people who have been given a placebo.

Cannabis and THC

The use of vaporized cannabis resulted in increased subjective alterations and a higher concentration of THC in the blood than with smoked cannabis (14.4 ng/ml, 10.2ng/ml). Besides, the study observes that the level of THC in the blood and cardiac activity reaches a peak 30 minutes after taking the drug and returns to normal about 3 to 4 hours after taking it. On the other hand, subjective, cognitive and psychomotor impairments persist for up to 6 hours after taking the drug.

The study notes that the maximum dose of the study, 25 mg THC (0.187g weed to 13.4% THC), is significantly lower than the dosage and concentration of conventional THC that can be found in pre-rolled joints in stores in the United States. In clinics, it is common to find joints containing 1 gram of cannabis with a THC concentration of more than 18%. The increasing availability of marijuana in the medical and recreational markets raises several questions that have not been addressed by research to date.

The discovery of this difference between vaporized and smoked cannabis (also show on this website vaporisateurcannabis.com) in adults who do not use cannabis regularly may inform the choice of health professionals in referring their patients or specific cannabis policies and regulations. These results can also be used to improve procedures for detecting severe cannabis poisoning.