CBD

CBD is the abbreviation of cannabidiol, a cannabinoid that the cannabis plant makes on its own, often in large amounts in hemp. Unlike THC, it does not produce the intoxication cannabis is known for. For most of its history the word was known only to chemists. Since the late 2010s it has been printed on oils, sweets, drinks, creams, flowers and prescription medicines, and it has become one of the hardest words for the law to place.

In the laboratory

Chemists tried to isolate the active ingredients of cannabis in the nineteenth century, and mostly got mixtures. Cannabidiol was first isolated in 1940, independently, by two groups: Roger Adams’s at the University of Illinois, working from the “red oil” of wild hemp gathered in Minnesota, and Alexander Todd’s at Manchester, working from cannabis resin. Adams’s team published in the Journal of the American Chemical Society in January 1940, and that August he filed a patent for the method. It was issued on 8 December 1942 as US 2,304,669, Isolation of Cannabidiol: the red oil is turned into a crystalline ester, which ammonia then splits to give the pure compound.

The patent prints a structural formula, and says plainly that it is incomplete: “with the exception of the position of the double bond in the left hand cycle”, the structure was taken as established. It also records that cannabidiol is “physiologically inactive so far as marihuana activity is concerned”, and that acids turn it into tetrahydrocannabinols that do have that activity. The 1942 drawing is not the modern structure. That was established in 1963 by Raphael Mechoulam and Yuval Shvo in Israel, using nuclear magnetic resonance, and the stereochemistry followed. Cannabidiol is now also the compound’s international non-proprietary name, the official generic name of a medicine; CBD is the shorthand that went to market.

From hemp to the high street

In the United States the 2018 Farm Bill removed hemp, defined as cannabis with no more than 0.3 per cent THC, together with its extracts and cannabinoids, from the federal drug law. Six months earlier, in June 2018, the Food and Drug Administration had approved a cannabidiol medicine, Epidiolex, for two rare forms of childhood epilepsy, Lennox-Gastaut and Dravet syndromes. Neither step made every CBD product legal. CBD foods and drinks had been on sale since about 2017. But CBD itself was never declared safe as a food ingredient, so selling it in food or as a dietary supplement stayed illegal under federal food law, and the FDA sent dozens of warning letters to companies selling it as a cure. Its own tests found many products mislabelled; in 2020 half of 147 products it studied contained THC.

The boom did not last. According to the Wikipedia account, the American CBD industry stalled during the pandemic and by 2024 had collapsed, for want of investors, of an FDA ruling and of consistent state laws.

What the law calls it

The same molecule is a medicine in one place, a food in another, a hemp product in a third and, under some conditions, a controlled drug.

Place	Year	What CBD became
Bulgaria	2019	A food supplement certified for open sale
Taiwan	2020	A medicine on prescription, with almost no THC allowed
Slovakia	2021	No longer a psychotropic substance
France	2022	Hemp flower lawful to sell, by order of the Council of State
China	2024	A precursor chemical under state control
Andorra	2025	A drug, if it contains any THC at all

In the European Union, the European Commission said in 2019 that CBD counts as a “novel food”, since it was not eaten before May 1997, and so needs a safety assessment before it can be sold as one. Sweden’s Supreme Court ruled the same year that CBD oil with any THC in it falls under the narcotics law. The Andorran case shows what that can mean: a resident caught at the border with half a kilo of flower sold as CBD spent more than a year in prison.

Hemp again

In November 2025 the US Congress rewrote the hemp definition from 12 November 2026, counting all THC and capping a finished product at 0.4 milligrams of THC per container. Its target was the intoxicating products that had grown up under the same hemp definition, such as delta-8.^{[1][2][3][4][5]}