Celecoxib is used for:

Treating rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, menstrual pain, or pain. It is used in familial adenomatous polyposis (FAP) to decrease the number of polyps (growths) in the rectal area. It may also be used for other conditions as determined by your doctor.

Celecoxib is a COX-2 inhibitor NSAID. Exactly how it works is not known. It may block certain substances in the body that are linked to inflammation. NSAIDs treat the symptoms of pain and inflammation. They do not treat the disease that causes those symptoms...