Constipation and nausea may be caused by indigestion, intestinal obstruction and intestinal tumor. 1. Indigestion: Eating a lot of meat, persimmons and other hard-to-digest food for a long time leads to indigestion, and food accumulates in the gastrointestinal tract, which causes constipation and nausea, so you should adjust your diet and eat more vegetables and well-digested food. 2. Intestinal obstruction: intestinal foreign bodies, parasites, fecaliths and intestinal thrombosis lead to intestinal obstruction, food discharge is blocked and accumulates in the intestines, resulting in constipation and nausea, and often abdominal pain and bloating. 3. Intestinal tumors: colon cancer, rectal cancer and other intestinal tumors lead to narrowing of intestinal lumen and obstruction of food transmission, which can lead to constipation and nausea, and there are often changes in stool properties. Constipation and nausea should go to the hospital and be treated according to the cause under the doctor’s guidance.