It's been a strange journey for the wonder drug. People have been using salicylic acid, found naturally in willow and myrtle, for almost as long as civilization has been around. Ancient Sumerian clay tablets mention using willow leaves to treat rheumatoid arthritis, and the Ebers papyrus, one of the world's oldest preserved medical texts,k indicates that the Egyptians knew of the analgesic properties of dried myrtle leaves from at least the middle of the second millennium B.C. The Greek physician Hippocrates wrote in the 5th century B.C. of willow bark's curative powers, sentiments later echoed by Galen and other Roman and Greek luminaries, and some evidence also suggests that ancient Chinese, Native American, and African groups were aware of the drug. WILLOW CONTINUED to be used well into the Middle Ages in Europe, only to tun into a major obstacle: the lumber business. The budding wicker industry needed the willow for itself; in fact, demand was so high that in some places using willow for medicinal reasons was banned outright. Even then, scientistswere still making some progress; in the mid-1700s, the Reverend Edward Stone wrote a note to the president of the Royal Society of London describing quantitatively the treatment of fever with powdered willow bark. He was motivated in part by the Doctrine of Signatures, a philosophical tenet that holds that plants offered external clues to the kinds of maladies, they might treat; willow is often found in moist soils, which were associated with fevers. But it would take war for aspirin to really return to the limelight. After the colonization of the New World, Europe had taken to treating pain and fever with quinine imported from South America. When Napoleon Bonaparte's rise to power plunged Europe into more than a decade of internecine conflict, however, naval clashes between Britain and France cut off much of the continental mainland from maritime trade. Napoleon and other leaders were forced to return to readily available sources of analgesics, such as willow. In the 1820s and 1830s, scientists succe3eded in isolating the active ingredient, salicin, from willow bark. The bitter extract garnered its name from the Latin designation for white willow, Salix alba; because of its acidity in water, the compound became more commonly known as salicylic acid. The compound was eventually produced industrially from coal tar through a process discovered by Herman Kohbe, but its nasty side effects - an unpalatable taste and stomach irritation-led many users to comment that the cure was worse than the disease. In 1897, a scientist at German firm Bayer, Felix Hoffman, created the modern form of aspirin by acetylating the hydroxyl group of salicylic acide, creating acetylsalicylic acid.

Mehta, Aalok. 2005June20. Aspirin. C&EN News. 83(25): pp. 46-47. [Excerpt and modified from this reference. ]

Updated: Saturday, December 29, 2007.