There were virtually no differences between men and women in their response to cannabis use, Lambert Initiative research has discovered, in results that differ from earlier studies.

The study of 21 men and 19 women identified no discernible variations across a range of measures including subjective drug effects, cognitive performance, cardiovascular effects and plasma concentrations of THC, CBD and relevant metabolites.

The effects of cannabis were largely the same for both sexes, although higher doses may produce different results, according to Lambert.

Other studies using different methodologies and varying cannabis strength have previously found evidence to suggest the sexes differ in their response to acute cannabis use.

“Some studies suggest that males and females respond to cannabis differently, while others suggest otherwise,” Lambert said. “It is important to assess for, and identify, sex differences so that treatments and policies can be designed in a way to be protective of both sexes.”

In the latest randomised controlled trials, participants – all occasional cannabis users – received 13.75mg of THC or CBD dominant vaporised cannabis, a balance, or a placebo.

While males performed better overall on a divided attention task and had a higher peak plasma concentration of 11-nor-9-carboxy-THC (11-COOH-THC), overall pharmacokinetics were largely the same. There was also no notable difference regarding subjective effects or cardiovascular measures.

The data indicates “an absence of systematic sex differences in acute cannabis effects given a moderate dose of vaporised cannabis”, the study concluded. It added sex differences may emerge with higher THC doses or with other routes of administration.

Lambert Initiative academic director Professor Iain McGregor said what differences there were bordered on the irrelevant.

Lambert Initiative
Professor Iain McGregor from the Lambert Initiative

“Sometimes in science, a nothing result is a very interesting result,” he said. “This analysis shows that for the male and female response to cannabis, the similarities far outweigh the differences in terms of subjective effects, cognitive effects, and blood THC and CBD concentrations.

“Any sex differences in this dataset are so subtle that they are probably not worth bothering about.”

However, Professor McGregor noted the study examined only one moderate dose of vaporised cannabis.

“It is possible that with higher doses, or with oral administration of cannabis products, or mixing cannabis with something like alcohol, you might start to see something,” he said.

The research body referred to recent analysis of a number of controlled studies which concluded women were more susceptible to subjective ratings of anxiety, nervousness and heart racing. But Lambert noted the average participants in those studies had not consumed cannabis for up to 280 days. Its recent work assessed more regular users.

“It is therefore likely that these participants would have been significantly more sensitive to acute cannabis effects than the participants analysed in the present study,” the report’s authors wrote.

“Moreover, significant sex differences only emerged in the high-dose conditions (20–25 mg THC), whereas participants in the present study received a maximum dose of 13.75 mg THC. This would suggest that sex differences in acute cannabis effects may be subtle in nature and less prominent at lower doses.

“Overall, the present analyses suggest that sex differences in acute cannabis effects, given a modest THC dose and administration via vaporisation to individuals with a history of prior but occasional cannabis use, are trivial, if indeed they are present at all.”

Steve has reported for a number of consumer and B2B titles over a journalism career spanning more than three decades. He is a regulator contributor to health journal, The Medical Republic, writing on...