Marijuana as medicine: Everything you need to know

Medical marijuana use is skyrocketing: between 2016 and 2020, the number of people in the US with a licence to buy it more than quadrupled, reaching nearly 3 million – a figure that excludes people self-medicating outside official programmes. There is a similar upward trend in Australia. In the UK, where medical cannabis was legalised in 2018, just 60 prescriptions had been issued by 2020, but an estimated 1.4 million people say they used it for medicinal purposes that year.

Humans have long used cannabis …