Since ancient times, therapeutic properties have been found in cannabis, and the plant, also called hemp, has been used for millennia on several continents. The Egyptians used it to reduce eye pressure or soothe gynecological inflammations, the Greeks considered it effective against ear infections, Chinese medicine praised its analgesic and anesthetic qualities in various medical treatises, and Indian tradition mentions it for treat migraines, epilepsy or anxiety.
The plant continued to arouse the curiosity of botanists over the centuries, but it was in the 19the century that it has benefited from a real revival of interest. Rediscovered during Bonaparte’s campaign in Egypt, and by the colonies in India and North Africa, cannabis became a subject of study.
In France, the psychiatrist Jacques-Joseph Moreau de Tours (1804-1884) was especially interested in its psychotropic properties. To better measure its effects, he also had his friends from Parisian artistic bohemia, gathered within the famous Hashish Club, consume it.
At the time, cannabis was not smoked but eaten, in the form of a greenish jam made from cannabis resin called “dawamesk”. Théophile Gautier has in his writings recounted the effects “intoxicating”.
Dethroned by opiates
At the same time, the Irish doctor William Brooke O’Shaughnessy (1809-1889), returning from Calcutta, popularized the medical use of cannabis in Great Britain. Cannabis tinctures (extracts diluted in an ethyl alcohol solvent) are prescribed to patients with rheumatism, to reduce convulsions induced by tetanus and rabies, or to treat pain, insomnia and migraines.
In the middle of the 19th centurye century, cannabis thus found its place in the Western pharmacopoeia (it remained in the French pharmacopoeia until 1953), and pharmacies prepared it at the time without being in any way worried. Hard to believe today, but Indian cannabis cigarettes were even sold at the time against asthma: Grimault cigarettes!
However, the medical use of the plant declined from the end of the 19th century.e century, dethroned by that of opiates, which doctors consider more effective against pain, and especially by the arrival of aspirin. The fate of the plant was definitively sealed when cannabis was included, alongside heroin, in Tables I and IV of the Single Convention on Narcotic Drugs of 1961, which list the most dangerous drugs considered not to have any therapeutic advantage likely to be used. The ban will not prevent some researchers from taking an interest in the plant. The Israeli chemist Raphael Mechoulam isolated and described the chemical structure of THC in 1964. His research will revive medical interest in cannabis, to which he will continue to devote himself until his death in March 2023.