Acute pancreatitis is inflammation of the pancreas. This occurs suddenly and will cause pain in the upper abdominal region through your back. You may also experience fever, nausea, vomiting, jaundice, diarrhea, and bloating. Acute pancreatitis has both direct and indirect causes such as immune system attacks, gallbladder stones, viral and bacterial infections, and certain medications. Excessive use of alcohol and tobacco increases your risk for developing acute pancreatitis, but this disease can affect any one at any time.