Nonsteroidal anti-inflammatory agents (usually abbreviated to NSAIDs) are a group of medicines that relieve pain and fever and reduce inflammation.
There are nearly two dozen different NSAIDs available, but they all work in the same way, and that is by blocking a specific group of enzymes called cyclo-oxygenase enzymes, often abbreviated to COX enzymes. These enzymes are responsible for the production of prostaglandins. Prostaglandins are a group of compounds with hormone-like effects that control many different processes such as inflammation, blood flow, and the formation of blood clots.
What are nonsteroidal anti-inflammatory agents used for?
NSAIDs are used to treat mild-to-moderate pain that arises from a wide range of conditions such as headaches, menstruation, migraines, osteoarthritis or rheumatoid arthritis, sprains and strains, and toothache.
Aspirin is a NSAID that is used in small doses to lower the risks of having a heart attack or a stroke caused by a blood clot. It may also be given as a single dose at the time of a heart attack to improve outcomes. This is because it irreversibly inhibits the COX-1 enzyme.
What are the differences between nonsteroidal anti-inflammatory agents?
NSAIDs may be grouped according to their preference for COX-1 and COX-2 enzymes. Those that favor COX-1 are more likely to cause gastrointestinal side effects. Those that favor COX-2 have a higher risk of cardiovascular effects but less gastrointestinal effects. Higher dosages of NSAIDs tend to result in more COX-2 enzyme inhibition (and more cardiovascular side effects), even in those NSAIDs traditionally seen as low risk (such as ibuprofen). NSAIDs with higher activity against COX-2 enzymes should be used with caution in people with cardiovascular disease or at increased risk of cardiovascular disease.
Both types of COX enzymes produce prostaglandins; however, the main function of COX-1 enzymes is to produce baseline levels of prostaglandins that activate platelets and protect the lining of the gastrointestinal tract, whereas COX-2 enzymes are responsible for releasing prostaglandins after infection or injury.
Most NSAIDs inhibit both enzymes to a certain extent.
