Rofecoxib is a nonsteroidal anti-inflammatory drug (NSAID) used for osteoarthritis to reduce pain and inflammation and to ease mild to moderate pain. Rofecoxib is in a class of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Rofecoxib is used to reduce pain, inflammation, and stiffness caused by osteoarthritis and rheumatoid arthritis; to manage pain in adults; and to treat menstrual pain.
Rofecoxib works by inhibiting prostaglandin production, primarily by the inhibition of cyclooxygenase-2. It does not inhibit cyclooxygenase-1, which supposedly makes it easier on the stomach than traditional NSAIDs. By inhibiting the activity of the enzyme cyclooxygenase-2 (COX-2), rofecoxib reduces the synthesis of prostaglandins that play a role in causing arthritis pain and inflammation. It does not inhibit the activity of COX-1, the enzyme involved in the synthesis of prostaglandins that help protect against stomach ulcers and other health problems.
NSAIDs work by blocking the action of a substance in the body called cyclo-oxygenase. Cyclo-oxygenase is involved in producing prostaglandins, in response to injury or certain diseases. These prostaglandins cause pain, swelling and inflammation. Because NSAIDs block the production of these prostaglandins, they are effective at relieving pain and inflammation.
Cyclo-oxygenase does not only produce prostaglandins that cause inflammation. It also produces prostaglandins that have useful roles in the body. There are two different forms of cyclo-oxygenase, COX-1 and COX-2. COX-2 is the form that (among other things) produces prostaglandins that cause inflammation. COX-1 does not produce inflammatory prostaglandins, but does produce others that have useful effects, including some that are involved in maintaining a healthy stomach and intestinal lining.
Traditional NSAIDs, such as ibuprofen or diclofenac, block the action of both COX-1 and COX-2, and this is why they can sometimes cause side effects such as stomach irritation and peptic ulcers. Rofecoxib belongs to a new generation of NSAIDs that selectively block the action of COX-2. This means that it stops the production of inflammatory prostaglandins, without stopping the production of prostaglandins that protect the stomach and intestines. It therefore reduces pain and inflammation, but is less likely than traditional NSAIDs to cause side effects on the stomach and intestines.
Rofecoxib is a white to off- white to light yellow powder. It is sparingly soluble in acetone, slightly soluble in methanol and isopropyl acetate, very slightly soluble in ethanol, practically insoluble in octanol, and insoluble in water. The empirical formula for rofecoxib is C17H14O4S, and the molecular weight is 314.36.