Cannabis is currently the most widely used illicit drug in Western populations.¹ The question of whether or not it should remain prohibited is under debate in many European countries. Possible adverse health effects play an important role in this debate. The classical anxiolytic, sedative, analgesic, and psychedelic properties of cannabis are well known,¹ but it has recently been suggested that it may also induce cerebrovascular disease.² Now for the first time, Mateo et al have shown (this issue, see page 435) that a causal relation with cerebrovascular events is …