The side effects of Celecoxib mainly involve the digestive system, the blood system, and the cardiovascular system. The generic name of Celecoxib is Celecoxib, which is a non-steroidal anti-inflammatory drug. Oral administration of Celecoxib may cause indigestion, abdominal pain, diarrhea, flatulence, nausea, and in severe cases, may cause ulceration, bleeding, or even perforation of the gastrointestinal tract. If you experience persistent upper abdominal pain, black stools or vomiting of blood while taking the drug, stop the drug immediately and visit your local healthcare provider. Because drinking alcohol or smoking may increase the risk of gastrointestinal bleeding, alcohol, smoking, and beverages containing alcohol should be avoided while taking the medication. Celecoxib can inhibit blood production, so if you experience bleeding gums, nasal bleeding, under-eye congestion, skin bruising, or black stools while taking the drug, discontinue the drug immediately and visit your local health care provider. Celecoxib may cause serious cardiovascular events, resulting in fatal heart failure. Therefore, if symptoms such as chest tightness, shortness of breath, weakness, slurred speech, or edema occur during the use of the drug, discontinue the drug immediately and go to the local regular medical institution.