Simple nausea without real vomiting can be seen in chronic gastritis, mild acute gastritis, hepatitis, cholecystitis and other diseases, or it can be a gastrointestinal reaction to renal insufficiency. If it occurs in women after intercourse, it may be due to pregnancy reaction and there is a possibility of pregnancy. You can first do blood and urine human chorionic gonadotropin, and gynecological ultrasound to rule out pregnancy. To rule out pregnancy, you need to do abdominal examination, hepatobiliary and pancreatic ultrasound, liver function and kidney function tests, and determine the cause according to the test results and medical history. Acute gastritis can be treated with antibiotics such as ciprofloxacin, chronic gastritis can be treated with drugs such as ranitidine and domperidone, while diseases such as hepatitis, cirrhosis and liver tumors should be treated in hospital, and cholecystitis can be treated with drugs such as chicken bone capsule. Renal insufficiency needs to be referred to nephrology for renal puncture and other tests, and treatment can be chosen according to the test results.