Cannabis: a controversial 21st-century drug of antiquity.

Cannabis consumption has been popular for thousands of years and its historical use is noted in many parts of the world including ancient China, India, the Middle East. It is currently the most popular illicit drug in the world, is being utilized as a medicinal plant, and many parts of the world are legalizing this drug. This discussion considers various aspects of cannabis use including its prevalence, history, co-morbid drug abuse, designer cannabinoids, psychiatric adverse effects, medical adverse effects, and management options. The youth of the world should be comprehensively taught that cannabis is neither a safe nor a benign drug. Prevention with comprehensive drug education is the best plan for our youth since management of a chronic or heavy cannabis consummer remains difficult and fraught with failure if cessation is the goal. Caveat emptor!