The Chemistry of Pain Relievers

4-hydroxyacetanalide, or acetominophen is commonly used in pain relievers such as Tylenol.

The structure of acetominophen

 Acetominophen works as a pain reliever by inhibiting the creation of prostaglandins, which are chemical messengers that transmit pain signals.  Acetominophen blocks the signaling of these prostaglandins, bot does not block some other characteristics of them.  An example of this is that prostaglandins promote the inflammation of body tissues during injury, and acetominophen does not inhibit the swelling.
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