Question: I was watching the news and a segment on the show was discussing heart disease. They mentioned that those at risk for heart disease should take aspirin daily. Because of this, aspirin is a ubiquitous drug that is sold to anyone over the counter. For this BQA I wanted to do a little research into aspirin including its history, mechanism of action, and potential side effects.
Answer: Acetylsalicylic acid, more commonly known as aspirin, is classified as a nonsteroidal anti-inflammatory drug (NSAID). NSAIDs are drugs that act as fever reducers, painkillers and anti-inflammatory agents when used in sufficient dosages. The properties of aspirin were first discovered at least 2400 years ago by Hippocrates who prescribed willow bark for headaches. Willow bark contains the active ingredient of aspirin – salicylic acid. It wasn’t until the 19th century that this active ingredient was synthesized by a chemist at Bayer. The mechanism of aspirin’s medicinal properties remained a mystery in the early 20th century despite its prevalence as a drug. The earliest attempts to explain its action is that aspirin relieved pain by acting on the central nervous system – referring to the brain and spinal cord. In the 1960s physicians and pharmacists discovered that this was untrue by showing that the drug only acted at the site of administration on guinea pigs. John Vane, a pharmacologist at the Royal College of Surgeons in England, eventually discovered the biochemical mechanism for the action of aspirin; he received a Noble Prize in Physiology and Medicine in 1982 for this work. He determined that aspirin works by inhibiting the synthesis of prostaglandins. Specifically, aspirin irreversibly deactivates the COX enzyme responsible for creating prostaglandins. This makes aspirin different as NSAIDs are typically reversible inhibitors. Prostaglandins are small, active, lipid (fatty-like) molecules which exhibit similar effects as hormones. Aspirin works by preventing prostaglandins from causing a pain/inflammation response. Aspirin has another effect; it prevents the production of thromboxane A2 in platelets which is also a result from inactivated COX enzyme. This has an inhibitory effect on platelet aggregation which will reduce a person’s risk of a heart attack. As a result, it is a drug prescribed daily to those at risk of heart disease. One caveat to this “wonder drug” is that it seems to have adverse effects on children – especially when the child has a viral infection. The exact cause of this is still unknown.
- Zeus the Sitar Lord
- Awtry EH, Loscalzo J. Aspirin. Circulation. 2000;101(10):1206-18.