Naproxen
also known as Accord, Aleve, Anaprox, Antalgin, Apranax, Feminax Ultra, Flanax, Inza, Maxidol, Nalgesin, Naposin, Naprelan, Naprogesic, Naprosyn, Narocin, Pronaxen, Proxen, and Soproxen
It was patented in 1967, and approved for medical use in the United States in 1976.
Naproxen is a slightly more long lasting painkiller than ibuprofen.
In much of the world it is a prescription-only drug but it is available over-the-counter in the US and UK. It can be used to treat painful periods or menstrual cramps.