Sudden loss of appetite: what to do

Appetite can change quickly when nausea, fever, pain, anxiety, or altered taste develops. Gastroenteritis may start with appetite loss and digestive symptoms; influenza and COVID-19 may do so with fever, aches, cough, or tiredness. Gastritis or peptic ulcer can make food uncomfortable. Depression may affect appetite and interest in meals, while hepatitis A can cause appetite loss with fatigue and nausea. The symptom alone cannot tell which explanation applies.

Think about what changed before the appetite loss: a new medicine, travel, contact with illness, emotional strain, or abdominal symptoms. This context helps a clinician decide whether observation or examination is appropriate.

Take small sips of water or another tolerated drink and try small portions when able. If nausea is present, bland foods and slower eating may be easier. Check whether you are passing urine normally and avoid alcohol. Review new medicines with a pharmacist or prescriber rather than stopping essential treatment on your own. If the change lasts, worsens, or prevents normal intake, arrange a medical appointment.

Get urgent help for severe abdominal pain, repeated vomiting, fainting, confusion, blood in vomit, black stools, breathing difficulty, or inability to keep fluids down. Seek prompt advice for yellow eyes or skin, marked weakness, very dark or infrequent urine, or a rapidly worsening illness. Children, older adults, and people with chronic conditions can become dehydrated sooner and should be assessed early.

Could a new medicine or infection explain this change? What signs should I monitor at home? How can I maintain fluids and food? Do my other symptoms require an examination or tests? When should I contact you again?