👉 Nausea is a sensation of abdominal discomfort or pain that occurs when there is an excessive release of stomach acid, which can cause nausea. It can be caused by various factors such as stress, anxiety, irritable bowel syndrome (IBS), and certain medications. Symptoms may vary from person to person, but they often include feeling nauseous, vomiting, diarrhea, bloating, or cramping in the abdomen.