Cardiovascular effects of cannabis (marijuana): A timely update

Cannabis (medical marijuana) is generally considered a low toxicity drug. The plant belongs to the family Cannabaceae (Urticales). Two main species may be recognized: Cannabis sativa and Cannabis indica. Plants of this species contain many psychoactive components, the cannabinoids, including the primary psychoactive compound Δ-9-tetrahydrocannabinol (THC), the active substance present in Marijuana. The history of its cultivation and use dates back thousands of years. A possible first documented use for medical purposes of this drug is found in Chinese records dated from 28th century BC. Moreover, the presence of THC has been detected in several internal organs from an Egyptian mummy with a ¹⁴ C-dating of approximately 950 BC. Evidence of therapeutic potential for marijuana and its components has been suggested for a large number of medical conditions. Despite this, a variety of cardiovascular complications have been documented. Dysregulation of the endogenous lipid mediators endocannabinoids and their G-protein-coupled cannabinoid receptors CB₁ and CB₂ has been, in fact, linked to different cardiovascular pathologies. Here, we describe a timely update of possible cardiovascular effects of its use for medical purposes.