Cannabis in both its pure and altered forms has been beneficial for human use since antiquity. 1 Members of the genus Cannabis mostly produce dioecious annual herbs. 2,3 The exact number of Cannabis species is a point of great debate, as according to different researchers there are variable number of species. 4-10 The species that are most pertinent include, Cannabis sativa, Cannabis ruderalis and Cannabis indica. However, among these, the highly polymorphic species Cannabis sativa L. is considered as the most active, based on studies targeting its morphology, anatomy, phyto-chemistry and genetics. 11 The morphological diversity of this plant is phenomenal, and it has tremendous potential as foodstuff and fuel (edible food/oil from its achene), fibre (stem) and pharmaceuticals. It also has unrivalled biochemical riches with regard to its considerable balance of active and biologically significant compounds and their potential medical uses. 12 History The history of C. sativa use dates back to over 10,000 years, supporting its recognition as one of the oldest domestic plants known to humanity. 7,13 It originated from Central Asia and is one of the oldest known psychotropic drugs. C. sativa was cultivated and consumed long before civilization; therefore, uncovering the origin of its use by humans is a difficult task. Archaeological discoveries have shown that it has been recognized and acknowledged since the Neolithic era in China, (around 4000 BC). 13 However the psychoactive potential of this plant was recognized by western medicine quite latter, with the year of 1839 seeing the first of its real description of actions. 14 China's Emperor Shen Nung wrote in his 2737 BC compendium the first description of the properties and medicinal uses of C. sativa. 14 Subsequently, it was cultivated for its fibre, fuel, seeds and medicinal purposes. 11 A distinguished surgeon in ancient China, Hua Tuo (115-205 AD), reportedly used cannabis as an anaesthetic. The analgesic and anaesthetic tendencies of C. sativa were also revealed in the biography of Chinese physician Hoa-tho, who practiced around 220 AD. 15 C. sativa then spread to the rest of the world, to ancient Egypt, prehistoric Europe, ancient Greece and
