The current scientific research and focus on cannabis as a medical preparation reinvents an ancient drug using modern scientific methods

First usages of cannabis

Cannabis has been grown and used by humans since at least 4000 BC. It was originally grown in China, mainly for use as food or fibres for strings, ropes, textiles, and paper. Cannabis was used for medical purposes in China, but extensive medical use occurred later in India, where it also came to be associated with religious rituals and recreational use. Cannabis subsequently spread to the rest of the world, including Europe, but during the 18th century, the plant was primarily grown in Europe for fibres, with fewer references to medical use1,2.

Introduction into Western medicine

The real introduction of cannabis into Western medicine came in the middle of the 19th century, when doctors began scientifically exploring its therapeutic use as well as its euphoric effects. Use of cannabis as medicine peaked in the second half of the 19th and early in the 20th century, and cannabis extracts and tinctures were marketed at this time by pharmaceutical companies like Merck, Bristol-Meyers Squibb and Eli Lilly for sedative, analgesic and appetite-stimulating effects1,2.

Cannabis as illegal drug

The medical use of cannabis declined during the 20th century. One reason for this might have been the wide variance in the content of different cannabis samples, which made it hard for the patients to control the effects. In addition, synthetic drugs were also given market approvals for many of the symptoms previously treated with cannabis. Legal restrictions on cannabis were also introduced in this period, limiting the use of cannabis for medical or scientific purposes. In spite of this, recreational and illegal use of cannabis rapidly spread amongst younger people in the Western world in the 1960s, leading to the reputation against which medical cannabis competes to this day – due especially to the uncontrolled breeding of plants, where the goal is to achieve the best ‘high’ for recreational use1,2.

Nowadays, a majority of patients who use cannabis for medical reasons obtain it through illegal sources3. There is no strict control of potency or contaminants, and the lack of medical advice poses additional risks. This makes it important for doctors to be well-educated with regard to the use, dosage and safety of medical cannabis, so that they can guide patients towards legal prescriptions and correct and safe administration.


1. Pisanti, S. & Bifulco, M. Medical Cannabis: A plurimillennial history of an evergreen. Journal of Cellular Physiology vol. 234 8342–8351 (2019).

2. Zuardi, A. W. History of cannabis as a medicine: A review. Revista Brasileira de Psiquiatria vol. 28 153–157 (2006).

3. Kvamme, S. L., Pedersen, M. M., Alagem-Iversen, S. & Thylstrup, B. Beyond the high: Mapping patterns of use and motives for use of cannabis as medicine. Nordic Studies on Alcohol and Drugs 38, 270–292 (2021).