O'Shaughnessy spent part of his career working in India, where he became interested in the medical uses for cannabis. One of his major works (On the Preparations of the Indian Hemp, or Gunjah) was published in 1843, and his trials showed the potential benefits of cannabis for conditions including cholera, rheumatic disease, and its palliative effect for rabies.
A French physician, Moreau traveled through North Africa in the 1830s and observed the use of hashish. He proposed that drug intoxication and hallucinations and delusions involved similar mechanisms, and conducted several experiments on the subject. In 1845, his book "Du hachisch et de l'aliénation mentale: études psychologiques" was published. Moreau is also considered a strong connection between cannabis and art, as "Club des Haschichins" (Hashish Club) included Dumas, Baudelaire, and others who served as subjects for his experiments. Jacques-Joseph Moreau (1804-1884).
Professors Raphael Mechoulam and Yechiel Gaoni identified the psychoactive component of marijuana and hashish in the Cannabis sativa plant:
Δ - 9 - tetrahydrocannabinol (THC).
Dronabinol (Marinol) is FDA approved for nausea and vomiting associated with cancer chemotherapy. In 1992 it is approved for weight loss among patients with AIDS.
Allyn Howlett's laboratory at St. Louis University provides the first evidence that cannabinoid receptors exist in the brain.
Dr. Lumir Hanus and Dr. William Devane discover the endocannabinoid anandamide. The subsequent discovery of additional endocannibinoids and their receptors revealed a system within the body capable of regulating numerous biological functions, known as the endocannabinoid system (ECS).
Members of the MRC Laboratory of Molecular Biology in Cambridge, UK discover a second cannabis receptor in the periphery.
California is the first state to permit legal access to cannabis under the Compassionate Use Act (Proposition 215). This allowed physicians to recommend medical marijuana for seriously ill patients, and gave patients and caregivers the ability to possess and cultivate medical marijuana.
The Institute of Medicine released a report entitled "Marijuana and Medicine: Assessing the Science Base" concluding there was sufficient scientific data to support the potential therapeutic value for cannabinoid drugs (THC) for several indications.
Results of the Cannabinoids in Multiple Sclerosis (CAMS) study, one of the largest randomized, placebo-controlled trials, is published. Six-hundred and thirty patients were treated at 33 centers in the UK with either oral cannabis extract with 2:1 ratio of THC and CBD, a synthetic THC formulation, or placebo. Physician-administered tests revealed no benefit of cannabinoids for spasticity, but patients reported improved sleep and spasticity compared to those receiving placebo.
The National Academies of Sciences, Engineering. and Medicine publish a report on the health effects of marijuana and derived products. The committee completed a rigorous review of scientific research pertaining to therapeutic effect and concluded there was evidence to support the use of cannabis and cannabinoids for pain reduction, as well as oral cannabinoids for multiple-sclerosis related muscle spasm and chemotherapy-induced nausea and vomiting.