Blood in mucus after vomiting: what to know

Forceful retching can scratch or inflame the throat and upper digestive tract, so a small bright streak may appear in saliva or mucus. Blood can also come from a nosebleed or irritated gums and mix with mucus during vomiting. Food poisoning and gastroenteritis may cause repeated vomiting that worsens irritation. Dark, grainy material can represent older blood rather than fresh throat spotting. Abdominal pain, fever, diarrhoea, dizziness and the amount of blood provide useful clues, but only an assessment can locate the source.

Stop eating briefly if vomiting continues, then try small sips of water or an oral rehydration drink when you can keep fluids down. Avoid alcohol and anti-inflammatory painkillers unless prescribed. Note whether blood is bright red, dark or mixed with food, and record episodes of vomiting, stool changes and urine output. Contact a clinician promptly, particularly if the blood returns, you take anticoagulants or you have a history of digestive disease.

Go to emergency care for a large amount of blood, repeated bleeding, coffee-ground-like material, black tarry stool, severe abdominal or chest pain, faintness, confusion, breathing difficulty, or inability to keep fluids down. Urgent assessment is also needed for severe dehydration signs such as very little urine, a dry mouth with worsening weakness, or unusual drowsiness. A stiff neck or severe headache with vomiting needs immediate help.

Ask whether the blood is more likely from retching, the nose or the digestive tract, whether you need tests, and how to replace fluids safely. Tell the clinician about recent illness, meals, medicines, alcohol and any abdominal pain.