The medical use of preparations derived from the Cannabis sativa plant has a long history. However, by the twentieth century, medical use of cannabis had largely declined, and its consumption for medical purposes was already very limited when in 1961 cannabis was included in the United Nations Single Convention on Narcotic Drugs and classified as a drug that had no medical uses (see ‘A brief history of the medical use of cannabis and cannabinoids’, on page 7). In the past 20 years, however, there has been a resurgence of patient interest in using cannabis and cannabinoids to treat a variety of conditions, including chronic pain, cancer pain, depression, anxiety disorders, sleep disturbances and neurological disorders, the symptoms of which are reportedly improved by using cannabis (NASEM, 2017).

Increased patient interest in the medical use of cannabis has been accompanied by renewed scientific interest in the medical use of substances found in the cannabis plant, namely cannabinoids. This followed the discovery, in the early 1990s, of a cannabinoid system in the human brain and body that was implicated in the control of important biological functions, such as cognition, memory, pain, sleep and immune functioning. However, the classification of cannabis as a drug without medical uses made it difficult to conduct clinical research (NASEM, 2017).

In the mid-1990s, citizens in several US states responded to patient demand for cannabis by passing referenda that legalised the medical use of cannabis for people with a variety of illnesses, such as chronic pain, terminal cancer and multiple sclerosis. A similar approach was later adopted in many other US states. In 1999, Canada introduced a medical cannabis programme that expanded over the subsequent decades in response to court decisions. In the early 2000s, Israel (2001) and the Netherlands (2003), and later other countries, such as Switzerland (2011), Czechia (2013), Australia (2016) and Germany (2017), legislated to allow the medical use of cannabis under specified conditions. Over a similar period, clinical trials have provided the basis for granting an authorisation for marketing in many EU Member States of a medicinal product, primarily based on cannabis extracts, that has proven effective in the treatment of muscle spasticity due to multiple sclerosis.

Most EU countries now allow, or are considering allowing, the medical use of cannabis or cannabinoids in some form. However, the approaches taken vary widely in terms of both the products allowed and the regulatory frameworks governing their provision. In this context, this report aims to provide a brief overview of current knowledge and the latest developments relating to medical use of cannabis and cannabinoids.

The report is intended to help a broad audience of interested readers, such as policymakers, practitioners, potential patients and the public, to understand the scientific, clinical and regulatory issues that arise when consideration is given to making cannabis or cannabinoids available to treat the symptoms of medical illnesses.