Loss of appetite and a bitter taste

A bitter taste may come from acid or bile reaching the mouth, particularly after meals or when lying down. Dry mouth, nasal congestion, poor oral hygiene and some medicines can change taste and reduce interest in food. Gastritis, gastroenteritis and viral illnesses may cause nausea alongside an unpleasant taste. Appetite loss is a common presentation of several conditions; the taste itself cannot identify which one is responsible.

Tell a clinician about heartburn, sour fluid, mouth soreness, blocked nose, vomiting, diarrhoea, fever, abdominal pain, new medicines and whether food tastes normal between episodes.

Drink water regularly, clean your teeth and tongue gently, and rinse your mouth after meals. Try smaller meals and remain upright after eating if reflux seems possible. Avoid foods or drinks that clearly worsen the taste, and do not stop prescribed medicines without advice. If nausea is present, select simple foods and take fluids in frequent sips.

Arrange a review if the taste or appetite change does not settle, interferes with eating, or follows a new medicine. Get urgent help for inability to keep fluids down, vomiting blood, black stools, severe abdominal pain, confusion, fainting, or yellow eyes or skin.

Ask whether reflux, oral dryness, infection or a medicine could explain the taste; whether your mouth and abdomen need examination; and how to protect nutrition while appetite is low.