In 1998, a small pharmacokinetic (PK) study failed to show that differences in a patients ability to clear naproxen from the body could account for differences in a patients risk of experiencing the adverse effect of a serious gastrointestinal bleed while taking naproxen. However, the study failed to account for differences in the activity of CYP2C9, a drug-metabolizing enzyme that is necessary for clearing naproxen. Studies on the relationship between CYP2C9 genotype and NSAID-induced gastrointestinal bleeds have shown that genetic variants in CYP2C9 that reduce the clearance of major CYP2C9 substrates (like naproxen) increase the risk of NSAID-induced gastrointestinal bleeds, especially for homozygous defective variants. Chemistry
Naproxen is a member of the 2-arylpropionic acid (profen) family of NSAIDs. The free acid is an odorless, white to off-white crystalline substance. It is lipid-soluble and practically insoluble in water. It has a melting point of 152–155 °C. Synthesis
Naproxen has been industrially produced by Syntex starting from 2-naphthol as follows:

Society and culture
Brand names
Naproxen and naproxen sodium are marketed under various brand names, including Accord, Aleve, Anaprox, Antalgin, Apranax, Feminax Ultra, Flanax, Inza, Maxidol, Nalgesin, Naposin, Naprelan, Naprogesic, Naprosyn, Narocin, Pronaxen, Proxen, and Soproxen. It is also available as the combination naproxen/esomeprazole magnesium in delayed release tablets under the brand name Vimovo. Access restrictions
Syntex first marketed naproxen in 1976, as the prescription drug Naprosyn. They first marketed naproxen sodium under the brand name Anaprox in 1980. It remains a prescription-only drug in much of the world.
See also
Beauty mark
List of Mendelian traits in humans
Melanocortin 1 receptor
Mole

References
External links

MedicineNet.com: Freckles
Ephelides (Freckles) at eMedicine