Naproxen sodium (INN) (pronounced /nəˈprɒksən/) is a nonsteroidal anti-inflammatory drug (NSAID) commonly used for the reduction of pain, fever, inflammation and stiffness caused by conditions such as osteoarthritis, kidney stones, rheumatoid arthritis, psoriatic arthritis, gout, ankylosing spondylitis, menstrual cramps, tendinitis, bursitis, and the treatment of primary dysmenorrhea. It works by inhibiting both the COX-1 and COX-2 enzymes. Naproxen and naproxen sodium are marketed under various trade names including: Aleve, Anaprox, Antalgin, Feminax Ultra, Flanax, Inza, Midol Extended Relief, Miranax, Nalgesin, Naposin, Naprelan, Naprogesic, Naprosyn, Narocin, Proxen, Synflex, Xenobid.
Naproxen was originally marketed as the prescription drug Naprosyn in 1976, and naproxen sodium was first marketed under the trade name Anaprox in 1980. It remains a prescription-only drug in much of the world. The U.S. Food and Drug Administration (FDA) approved the use of naproxen sodium as an over-the-counter (OTC) drug in 1994, where OTC preparations are sold under the trade name Aleve. In Australia, packets of 275 mg tablets of naproxen sodium are Schedule 2 Pharmacy Medicines, with a maximum daily dose of 5 tablets/1375 mg. In the UK, 250 mg tablets of naproxen were approved for OTC sale under the brand name Feminax Ultra in 2008, for the treatment of primary dysmenorrhoea in women aged 15 to 50. Aleve became available over-the-counter in most provinces in Canada on July 14, 2009 with the exception of British Columbia, Quebec and Newfoundland and Labrador, although it later became available without a prescription in these provinces.