Nausea and vomiting on an empty stomach are usually caused by chronic pharyngitis, hypertension, improper diet or digestive diseases, as follows: 1. chronic pharyngitis, chronic pharyngitis is a chronic inflammation of the mucous membrane in the throat, patients will feel a foreign body, itching or pain in the throat, accompanied by nausea and vomiting, especially in the morning when the symptoms of nausea and vomiting will be more obvious. 2. hypertension, mostly seen in Patients with hypertension will experience dizziness, headache, nausea and vomiting when their blood pressure rises, especially in the morning when they first wake up. 3, improper diet, overeating, irregular diet or eating too much stimulating food, such as spicy and stimulating food, too cold and too hot food, coffee, strong tea, etc., so that the gastric mucosa is damaged. 4, suffering from digestive system diseases. For example, acute and chronic gastritis, gastric ulcer, reflux esophagitis, duodenal ulcer.