Post-Surgery
Patients who have just undergone surgery [3] often complain about nausea. There are several reasons for feelings of nausea and vomiting after having an operation. For example, anesthesia has been linked to feelings of nausea post-operation. Anesthesia is a medicine inhaled right before surgery to induce a state of partial or complete loss of awareness and prevent the patient from feeling intense pain during the operation. After surgery, and the anesthesia wears off, you may feel [4] nauseous and vomit, lasting only for a few hours or a couple of days.
Another factor that may cause nausea is the rushed feeling of pain at the incision spot immediately after the anesthesia wears off. This pain may cause stomach discomfort, leading to feelings of nausea.