Ancient and medieval physicians mixed the plant into medicines or teas to treat pain and other ailments; back then, it wasn’t a highly controlled substance the way it is today, where in the U.S. it’s listed as a Schedule I drug along with LSD and heroin. Here’s a brief history of medical cannabis to better understand the level of its efficacy in treatments and therapies.

ANCIENT

2737 B.C. According to Chinese legend, Emperor Shen Neng was one of the first major leaders in the ancient world to officially prescribe marijuana tea to treat various illnesses — including gout, rheumatism, malaria, and poor memory, according to Understanding Marijuana: A New Look at the Scientific Evidence.

1550 B.C. Ancient Egypt’s Ebers Papyrus makes note of medical cannabis as a way to treat inflammation.

100 A.D. In ancient China, the Shennong Bencaojing, a medical book, refers to cannabis as “dama” and notes that the flowers, the seeds, and the leaves of the plant can be useful in medicine.

200 A.D. Hua Tuo, a Chinese surgeon, is the first recorded physician to use cannabis as an anesthetic during surgery. Hua Tuo ground the plant into powder, then mixed it with wine for a patient to drink before surgery. Interestingly, the word for anesthesia in Chinese, mázui, literally means “cannabis intoxication.” During this time, Chinese physicians also used the root, leaves, and oil of cannabis to treat blood clots, tapeworms, constipation, and even hair loss.

MEDIEVAL

100-1000s A.D. During the Middle Ages in Europe, cannabis may not have been a religious or spiritual hallucinogen like it was in India, but it was still integrated in folk medicine. Cannabis was used to treat tumors, cough, and jaundice.

MODERN

1500s. The Spanish brought cannabis to South America, but during the North American colonization, there was only hemp — used for practical purposes like clothes, bagging, paper, and ropes for the maritime industry. The hemp industry largely relied on slave labor, and cannabis wasn’t introduced to America as a psychoactive or medicinal drug until years later.

Late 1700s. At this point in time, some American medical journals were suggesting using hemp seeds and roots to treat various health problems, including skin inflammation and incontinence. William O’Shaughnessy was an Irish doctor in the British East India Company who touted medical marijuana’s benefits for rheumatism and nausea in England and America.

1906. During this time, Mexican immigrants entering the U.S. introduced marijuana to the country (and the word “marijuana” itself likely originated in Mexico), popularizing the recreational use of the drug more. However, many Americans saw those who smoked weed as debaucherous and troublesome, associating cannabis with “lower class” criminality.

1970. Marijuana was categorized as a Schedule I drug along with more dangerous ones, and was listed as having no accepted medical use. Despite the fact that some early American medical journals had begun listing the medical uses of cannabis, the government restricted any further research into it until more recently.

As of August 2023, 41 states in the U.S. have legalized medical cannabis, but only people with certain qualifications can obtain it.