Why Marijuana Effects Are So Unpredictable: Why are the effects of marijuana so unpredictable? Jonah Lehrer takes a look at why THC can do everything from make us paranoid to make us want multiple bags of potato chips.
The ratio of THC to cannabidiol seems to be the key variable: Skunk-type strains, for instance, contain a higher ratio of THC to cannabidiol than, say, hashish.
The basic moral of these studies is that the endocannabinoid system is tightly interwoven with the stress system. For instance, it’s long been recognized that stressing out a male newt leads, not surprisingly, to a rapid surge of corticosterone, a stress hormone. As a result, these poor males have little interest in sex, even when exposed to a lovely female newt. Here’s where the data gets surprising: The effects of the stress hormones seems to be mediated by the endocannabinoid system, so that when these endocannabinoid receptors are blocked stress has no effect. The males keep on having sex, even though they’ve just been through the ringer.
The reason marijuana has been around for thousands of years (and remains one of the most popular drugs in the world) is that it acts on an incredibly important neural system. EC receptors sit at the intersection of appetite and stress, pain and and anxiety.