Side effects can include: Feeling sick (nausea), vomiting, heartburn, indigestion, uncomfortable feeling or pain in the stomach, diarrhoea, swelling of the legs, ankles or feet, high blood pressure, dizziness, headache, allergic reactions including rash, itching and hives. Severe skin reactions, which may occur without warning, taste alteration, wheezing, insomnia, anxiety, drowsiness, mouth ulcers,diarrhoea, severe increase in blood pressure. Confusion, hallucinations, platelets decreased.
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. Etoricoxib 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 (although such side effects are still possible). This medicine can be taken with or without food, but may start to work quicker if taken without food.