Gastroenteritis and loss of appetite: what to know

During gastroenteritis, the stomach and intestines may be irritated, and nausea, abdominal discomfort, fever or diarrhoea can suppress the desire to eat. Appetite often returns gradually as vomiting and bowel symptoms ease. Loss of appetite that starts before digestive symptoms, lasts well beyond recovery, or comes with ongoing weight loss has a wider range of possible causes, including Gastritis, Hepatitis A, Influenza or COVID-19. Depression can also reduce interest in food. These possibilities cannot be distinguished from appetite change alone.

Fluids matter more than a full meal during the early phase. Take frequent small sips, and consider an oral rehydration drink if vomiting or diarrhoea is causing fluid loss. When you feel able, try small portions of bland or familiar foods, such as soup, rice, toast, yoghurt or bananas, adjusting to what you tolerate. Avoid forcing food or making large dietary changes. Keep track of drinking, urination, vomiting, stools and appetite so a clinician can see whether recovery is progressing.

Contact a clinician if you cannot drink, are urinating much less, feel faint, have persistent vomiting, severe abdominal pain, blood in vomit or stool, yellowing of the skin, or a fever that does not settle. Arrange an appointment for appetite loss with ongoing weight loss, marked tiredness, night symptoms, or no clear improvement after the infection has passed. Seek urgent help for confusion, collapse or signs of severe dehydration.

Ask whether your symptoms fit Gastroenteritis, how to replace fluids and food safely, and whether medicines could be affecting appetite. Mention weight change, mood, travel, sick contacts, alcohol, new foods, abdominal pain and the duration of each symptom.