There are numerous reasons why a rabbit may stop eating. Regardless of the cause, this is a very serious concern and can become fatal if left untreated. Dental disease, infection, urinary tract disease, and E. cuniculi are just a few common diseases that may induce an episode of GI stasis. When this occurs, the intestines stop working, and your rabbit may develop a generalized infection called sepsis. Please see your veterinarian immediately if your rabbit stops eating.