History
As early as the Hippocratic era in ancient Greece, people used willow leaves and other plants to treat inflammation. Later, salicin was extracted from these plants. Salicin is a precursor to salicylic acid. Salicylic acid is often used to treat arthritis, but it is difficult to ingest and has strong gastric side effects. In 1899, Felix Hoffman, a chemist at Bayer Pharmaceuticals, added an acetyl group to salicylic acid, synthesizing acetylsalicylic acid, which is aspirin.
Its unique acetyl structure is the only one among the eight types of nonsteroidal anti-inflammatory drugs (NSAIDs) that irreversibly inhibits cyclooxygenase.
Medical Use
Antipyretic, analgesic, anti-inflammatory: inhibits cyclooxygenase (COX)
- Antipyretic
- Analgesic
- Anti-inflammatory
Anticoagulant: Prostaglandins produced by platelets and vascular endothelial cells are very important for blood coagulation. Cyclooxygenase in platelets produces pro-coagulant prostaglandin TxA2, while vascular endothelial cells produce anti-coagulant prostaglandin PGI2. Platelets lack a nucleus and cannot produce new RNA to synthesize pro-coagulant prostaglandins, so once inhibited irreversibly by aspirin, this platelet function is lost until new platelets are produced (about one week). Meanwhile, vascular endothelial cells continuously produce anti-coagulant prostaglandins. Overall, aspirin exerts an anticoagulant effect.
Side Effects
- Damage to the gastric mucosa
- Allergies
- Exacerbation of asthma
- Reye’s syndrome (usually appears after viral infections such as influenza or chickenpox recovery; about 90% of pediatric cases are associated with aspirin use) — can be substituted with acetaminophen