Raphael Mechoulam: The Israeli Chemist Who Quietly Built Cannabinoid Science

Raphael Mechoulam was born in Sofia, Bulgaria in 1930, into a Sephardic Jewish family that survived the Holocaust by moving to a series of progressively safer towns. After the war, the family emigrated to Israel. Mechoulam studied chemistry, did his army service, completed a doctorate at the Weizmann Institute, and took a research position at the Hebrew University of Jerusalem.

In 1963, he made a small request that changed his life. He asked the Israeli national police for some confiscated hashish.

He wanted to do something nobody had quite gotten right yet: figure out what cannabis actually was, chemically. Other researchers had tried. Most had isolated mixtures, partially characterized compounds, or worked with such impure samples that their conclusions were unreliable. Mechoulam wanted to start clean.

The police gave him five kilograms of seized Lebanese hashish. He carried it back to his lab on a public bus.

The Two Discoveries

Within a year, Mechoulam and his team had isolated cannabidiol — CBD — and figured out its full chemical structure. The next year, they did the same for tetrahydrocannabinol — THC. For the first time, the world had a clean, characterized version of the molecule responsible for cannabis's psychoactive effects. It became possible to study, dose, and synthesize it.

These two discoveries — CBD in 1963, THC in 1964 — are the foundation of essentially all modern cannabinoid science. Every subsequent piece of research, from drug development to receptor mapping to the modern legal cannabis industry, traces back through Mechoulam's lab in Jerusalem.

He did not stop there.

The System Underneath

Through the 1970s and 1980s, Mechoulam pursued a question that other researchers had dismissed as too speculative: if THC produced such specific effects, what was it binding to? In 1988, the Howlett lab at St. Louis University identified the first cannabinoid receptor, CB1. The race was on to find what the body itself was using to activate it.

In 1992, Mechoulam's lab — with the American researchers Bill Devane and Lumír Hanuš — isolated the first endogenous cannabinoid from pig brain tissue. They named it anandamide, from the Sanskrit ananda, meaning bliss. Three years later, they identified a second endocannabinoid, 2-AG.

These discoveries established that the body has its own cannabinoid signaling system, with receptors and messenger molecules that exist independently of the cannabis plant. The plant is, in effect, hitchhiking on a network that was already there.

The Long View

Mechoulam was famously modest about all of this. In interviews, he liked to point out that he had simply been the first one to look carefully. He was deeply curious, mildly skeptical of the more extravagant medical claims made for cannabis, and convinced that the right way to advance the field was through rigorous chemistry and unsensational research.

He worked into his nineties. He continued publishing papers on minor cannabinoids, on the entourage effect, on potential therapeutic applications, almost until his death. His lab trained generations of researchers who now run cannabinoid programs around the world.

He died in March 2023, at 92, in Jerusalem.

What He Built

The legal cannabis industry that exists today — the dispensaries, the regulated markets, the FDA-approved CBD medications, the academic departments, the clinical trials — exists because, in the 1960s, an Israeli chemist with five kilos of confiscated hashish took the time to figure out what was actually inside the plant.

He never made the kind of money the field he founded now generates. He worked in a state-funded university lab in a small country, on a problem most chemists considered fringe, for sixty years.

The molecule of bliss is named for the Sanskrit word for bliss because Raphael Mechoulam thought the molecule deserved a name with some weight. He was usually right about the weight of things.