What aspirin was first developed to treat
Aspirin, or acetylsalicylic acid, was created in 1897 by Felix Hoffmann at Bayer to relieve pain and reduce fever more effectively than salicylic acid, which came from willow bark and caused stomach irritation.[1] Bayer marketed it as a safer alternative for rheumatism, headaches, and general aches.
Why willow bark led to aspirin
Ancient Egyptians and Greeks used willow bark for pain around 400 BC, noting its fever-reducing effects. Native Americans applied it for similar reasons. In the 1800s, scientists isolated salicin from willow, then salicylic acid, but it irritated the gut. Hoffmann acetylated it to make aspirin, solving that issue while keeping the analgesic and antipyretic properties.[1][2]
How Bayer turned it into a blockbuster drug
Bayer patented aspirin in 1899 and sold it worldwide as a powder, then tablets. It quickly became popular for colds, flu, and arthritis pain. By 1915, Bayer dropped the patent in the US to boost sales, leading to generic versions.[2]
Original claims vs. modern understanding
Bayer promoted aspirin as a 'wonder drug' for pain, fever, and inflammation without specifics on mechanisms. Today, it's known to inhibit COX enzymes, blocking prostaglandin production that causes pain and fever. It wasn't originally intended for heart protection—that discovery came in the 1970s via anti-platelet effects.1
When did its use expand beyond the original purpose?
By the early 1900s, doctors used it for gout and infections. The heart disease link emerged in 1971 when Irish researchers showed it prevented blood clots. Low-dose aspirin for cardiovascular prevention became standard in the 1980s.3
[1]: https://www.acs.org/education/whatischemistry/landmarks/aspirin.html
[2]: https://www.history.com/this-day-in-history/february-1/bayer-patents-aspirin