Marijuana was America’s number-one analgesic for 60 years before the rediscovery of aspirin around 1900. From 1842 to 1900, cannabis made up half of all medicine sold, with virtually no fear of its high.
The 1839 report on the uses of cannabis by Dr. W.B. O’Shaugnessy, one of the most respected members of the Royal Academy of Science, was just as important to mid-19th century Western medicine as the discoveries of antibiotics (like penicillin and Terramycin) were to mid-20th century medicine.
(Transcripts, Ohio State Medical Society 15th annual meeting, June 12-14, 1860, pg. 75-100.)
From 1850 to 1937, the U. S. Pharmacopoeia listed cannabis as the primary medicine for more than 100 separate illnesses or diseases.
During all this time (pre-1000 B.C. to 1940s A.D.), researchers, doctors and drug manufacturers (Eli Lilly, Parke-Davis, Squibb, etc.) had no idea what the active ingredients of cannabis were until Dr. Mechoulam discovered THC in 1964.