Prof. Raphael Mechoulam, father of Israeli cannabis research, dies at 92

The Bulgarian-born scientist will be remembered for his many contributions to the field of medicinal cannabis.


When the Hebrew University of Jerusalem organic chemist Prof. Raphael Mechoulam was investigating cannabis (marijuana) in the 1960s, it was regarded as a psychoactive drug for getting high but that had no medical benefits.

Yet it so intrigued the Bulgarian-born researcher that he spent his academic life studying it and became a leading expert on medical cannabis.

HU president Asher Cohen said that most of the human and scientific knowledge about cannabis was accumulated thanks to Prof. Mechoulam.

“He paved the way for groundbreaking studies and initiated scientific cooperation between researchers around the world,” he said. “Mechoulam was a sharp-minded and charismatic pioneer.”

He and his research team isolated Δ 9-tetrahydrocannabinol (THC), the psychoactive chemical found in marijuana, an active ingredient that offers a variety of medicinal benefits including pain relief.

Prof. Raphael Mechoulam 521 (credit: Sam Sokol)Prof. Raphael Mechoulam 521 (credit: Sam Sokol)

Today, medical cannabis grown and processed without the psychoactive effects has been formulated to provide symptom relief without the intoxicating, mood-altering effects connected to recreational use of marijuana. It is sold in pharmacies around the country, with more than 110,000 license holders according to the Israeli Medical Cannabis Agency (IMCA), operating under the auspices of the Health Ministry.

It is not only smoked but is available in the form of oil, powder, dried leaves and more. The drug is given to relieve not only severe and chronic pain, but also Alzheimer’s disease, multiple sclerosis and muscle spasms, amyotrophic lateral sclerosis (ALS), HIV/AIDS, Crohn’s disease, epilepsy and seizures, glaucoma, severe nausea or vomiting caused by cancer treatment.

It has been prescribed even in a cocktail of low-dose-THC and a high-dose of cannabidiol (CBD) as an effective treatment option for managing symptoms associated with autism, leading to a better quality of life for both the patient and the caregivers.

When Mechoulam sought to obtain samples in the ’60s, he carried five kilos of “superb, smuggled Lebanese hashish” on a bus from Tel Aviv to Rehovot in the hope that he would not be apprehended. Still, cannabis research was easier to conduct in Israel than the more restrictive US.

His life

He was born in Sofia, Bulgaria, in November 1930, the son of a doctor and hospital director and a mother from a wealthy Jewish family. His father was taken by the Nazis to a concentration camp, and after the Communists took over parts of Bulgaria, he and his family emigrated to Israel in 1949, by which time Mechoulam had earned a degree in chemical engineering.

After his aliyah, he earned a master’s degree from HU in biochemistry, followed by a thesis on steroid chemistry to earn a doctorate at the Weizmann Institute of Science in Rehovot. After two years of postdoctoral studies at the Rockefeller Institute in Manhattan, he returned to the Weizmann Institute for five years and then returned to HU, where, in 1972, he became professor and the Lionel Jacobson Professor of Medicinal Chemistry three years later.He was named by HU as rector and then pro-rector, posts he filled for a total of six years.

In 1994, he was elected a member of the Israel Academy of Sciences and Humanities, and was one of the founding members of the International Cannabinoid Research Society and the International Association for Cannabinoid Medicines.

His 90th birthday was marked at a four-day symposium during the 31st International Cannabinoid Research Symposium, which Mechoulam helped to establish. It was held in Jerusalem for the first time.

Mechoulam received a large number of significant honors and awards. Twenty-three years ago, he was awarded the Israel Prize in Exact Sciences – Chemistry, and, more recently, the Harvey Prize of the Technion-Israel Institute of Technology in Haifa.