The answer: Men.
Men have greater pain relief after smoking marijuana than women, according to a Columbia University Medical Center study published online in Drug and Alcohol Dependence.
“These findings come at a time when more people, including women, are turning to the use of medical cannabis for pain relief,” said Ziva Cooper, PhD, associate professor of clinical neurobiology (in psychiatry) at CUMC.
“Preclinical evidence has suggested that the experience of pain relief from cannabis-related products may vary between sexes, but no studies have been done to see if this is true in humans,” Dr. Cooper added.
The Columbia University researchers analyzed data from two double-blinded, placebo-controlled studies that looked at the pain relief effects of cannabis in 42 recreational marijuana smokers. Study participants smoked an equal amount of either an active or a placebo form of cannabis, and then immersed one hand in very cold water until the pain could no longer be tolerated. Thereafter, the study participants completed a questionnaire about pain from the cold water.
Men reported a significant decrease in pain sensitivity and an increase in pain tolerance after smoking the active cannabis. Conversely, women did not experience a significant decrease in pain sensitivity. They did, however, report a small increase in pain tolerance after smoking active cannabis.
With respect to how intoxicated men and women felt after smoking the equal amounts of cannabis, there was no difference between the two sexes. There was also no difference in how each sex reported liking the effect of the active cannabis.
The researchers highlighted that additional studies in both sexes are needed to understand the factors that impact the analgesic effects of cannabinoids, which are the active chemicals in cannabis products, including strength, mode of delivery, frequency of use and type of pain measured.
“This study underscores the importance of including both men and women in clinical trials aimed at understanding the potential therapeutic and negative effects of cannabis, particularly as more people use cannabinoid products for recreational or medical purposes,” said Dr. Cooper.