By the late 19th century, cannabis was an important component of British and American physicians’ pharmacopoeia. When scientists at the French pharmaceutical company Sanofi-Aventis (now Sanofi) understood that THC could whet a user’s appetite, they created a weight-loss drug that blocked CB1 receptors, hoping to suppress appetite. Two years later, regulators pulled it from the marketplace because of its severe side effects, including depression and suicidal behavior. The episode seems to exemplify endocannabinoids’ importance to our sense of well-being and the difficulty of manipulating them therapeutically.

The epilepsy drugs that had been approved to date, none of which had helped Ben much, typically targeted the same few ion channels and receptors on the surface of neurons. But CBD worked on different and still somewhat mysterious pathways.

If she could find a suitable CBD extract, Jacobson thought, she might have a truly new class of drug for Ben. The other experimental drugs and devices she had heard about at epilepsy conferences were under development, unapproved by the F.D.A. and thus largely unavailable. But medical marijuana had been legal in California since 1996, so CBD was theoretically accessible right away. Still, it’s important to proceed cautiously until more randomized controlled trials are underway.

Attempts to increase native cannabinoids with synthetic drugs have fared no better. In 2016, French scientists halted a study of a drug designed to boost endocannabinoids. For reasons that remain unclear, six patients who took the medicine, meant to treat pain, were hospitalized.

Yet when 30 American Medical Association members were surveyed, starting in 1929, 29 disagreed with claims about the dangers posed by cannabis. One said the proposals to outlaw it were “absolute rot.” organic hemp oil But the hysteria Anslinger helped stir up worked politically. High taxes made cannabis much more expensive and difficult to obtain decades before President Nixon — scientists of his era disagreed with him, too, about marijuana’s supposed dangers — signed the Controlled Substances Act of 1970. A plant that people had used medicinally for thousands of years was now driven underground.

The rate and scale of research has not kept pace with the interest, says Hill, who believes there is little motivation to invest in studies because people are buying the products regardless. Short for cannabidiol, CBD is a non-intoxicating chemical in the cannabis plant. Unlike THC (tetrahydrocannabinol), CBD does not make you high. But CBD is gaining a reputation as as a magical elixir to treat everything from anxiety to depression, inflammation to acne.

Anslinger disdained Mexican-Americans and African-Americans. Modern scholars argue that his demonizing cannabis both justified his position and provided a way for him to gain legal leverage over peoples he despised. The high cost paid by people of color, once he had begun what we now call “the war on drugs,” may not have been an incidental byproduct of his efforts but an unstated goal from the start. Cannabis made people crazy, violent and prone to criminal behavior, Anslinger said. After O’Shaughnessy published his treatises on the plant, its use spread rapidly among physicians.