Plant extracts containing the active ingredient in aspirin have been used medicinally since at least 400 B.C., but the modern drug known as aspirin was first developed and patented by Bayer, a German pharmaceutical company. Bayer coined and trademarked the name "Aspirin."
Willow bark and the meadowsweet flower were used historically to treat headaches, pain and fevers. By the 19th century, the active ingredient in these plants had been isolated and named salicin.
In 1897, Bayer began to produce a remedy containing acetylsalicylic acid, a derivative of salicin. By the 1930s, Bayer's patents had run out, and aspirin became a generic drug.