How it began
On August 10, 1897, Felix Hoffmann, a chemist in the pharmaceutical laboratory of Friedrich Bayer & Co. in Elberfeld, prepared the first sample of pure acetylsalicylic acid. The customary story, first printed in 1934, says he was seeking a medicine for his rheumatic father. In 1949 his former colleague Arthur Eichengrün claimed the work was done under his direction, and a later analysis of archival material published in the BMJ supports that claim. Bayer marketed the drug in 1899 under the trademark Aspirin.
Before it existed
The pain-relieving and fever-reducing properties of willow bark had been known since antiquity. Salicylic acid was isolated from the bark in the early 19th century, Hermann Kolbe determined its structure and synthesized it in 1859, and the Heyden Company near Dresden began making it in 1874. It irritated the stomach, and some patients could not tolerate it. Acetylsalicylic acid had been synthesized earlier by a French and then a German chemist, but not in a pure, stable form.
How it works
Hoffmann added an acetyl group to salicylic acid, a strategy of "acetylating" molecules that Bayer chemists were using to improve the strength or reduce the toxicity of active substances. The resulting acetylsalicylic acid was found to be an analgesic, fever-reducing, and anti-inflammatory substance. The name Aspirin combines A for acetyl with spirin from Spirea, a genus of shrubs that is another source of salicylic acid.
How it spread
Bayer marketed the drug aggressively worldwide and obtained a United States patent, which gave it a monopoly on manufacture there from 1900 to 1917. Bayer's American plants were sold in 1919 as part of the reparations after World War I. The buyer, Sterling Products, was unable to protect the trademark, and aspirin became a staple of the over-the-counter market in the United States and elsewhere. More than 100 years after its invention, aspirin continues to be a popular over-the-counter drug, with uses extending far beyond those envisaged by its creators.
Who pushed back
The pharmacologist responsible for verifying the results was skeptical at first. Bayer's application for a German patent was rejected because the compound had been synthesized before. The question of credit also remained contested: the Science History Institute notes the suggestion that Eichengrün was left out of the story as told since the 1930s because he was Jewish.
