Benzenepropanoic acid, α-hydroxy-β-methoxy-β-phenyl-, (αS)-, commonly known as naproxen, is a nonsteroidal anti-inflammatory drug (NSAID) used to alleviate pain, fever, and inflammation. It acts by reducing prostaglandin levels in the body and is effective for various conditions including headaches, arthritis, menstrual cramps, and muscle aches. Available in prescription and over-the-counter forms, it is often recommended for long-term use in managing chronic conditions.