History of aspirin other studies from the 1960s to the 1980s established aspirin's efficacy as an anti-clotting agent that reduces the risk of clotting diseases. Aspirin sales revived considerably in the last decades of the twentieth century, and remain strong in the twenty-first with widespread use as a preventive treatment for heart attacks and strokes. Medicines derived from willow trees and other salicylate-rich plants have been part of pharmacopoeias at least dating back to ancient Sumer. The Ebers Papyrus, an Egyptian medical text from ca. 1543 BCE, mentions use of willow and myrtle (another salicylate-rich plant) to treat fever and pain. Willow bark
History of aspirin positive results came in and enthusiasm grew, Bayer sought to secure patent and trademark wherever possible. It was ineligible for patent in Germany (despite being accepted briefly before the decision was overturned), but Aspirin was patented in Britain (filed 22 December 1898) and the United States (US Patent 644,077 issued 27 February 1900). The British patent was overturned in 1905, the American patent was also besieged but was ultimately upheld. Faced with growing legal and illegal competition for the globally marketed ASA, Bayer worked to cement the connection between Bayer and Aspirin. One strategy it developed was to switch from