Throwing up blood from food poisoning

Food poisoning commonly causes nausea, vomiting, diarrhoea, abdominal pain, or fever. Repeated forceful vomiting can irritate or tear small blood vessels in the throat, but bloody vomit can also signal bleeding elsewhere in the digestive tract. The presence of diarrhoea or fever does not establish that food poisoning is the only cause. Record when symptoms began, what was eaten, whether anyone else became ill, and whether the blood was red or looked like coffee grounds. Blood in stool, severe pain, or reduced urination raises concern for dehydration or another serious problem.

Stop solid food for the moment if vomiting is continuing, and take small frequent sips of water or an oral rehydration solution if you are fully alert and can keep fluids down. Do not force fluids during repeated vomiting. Avoid anti-diarrhoeal or anti-inflammatory medicines unless a clinician recommends them. Keep a sample or photograph only if this does not delay care. A clinic may use oral rehydration therapy; IV fluid therapy may be needed when dehydration is significant or drinking is not possible.

Seek emergency care now for repeated or heavy bleeding, faintness, confusion, severe abdominal pain, a swollen abdomen, blood in stool, very little urine, inability to keep fluids down, or breathing difficulty. Children, older adults, pregnant people, and anyone with a long-term illness may become dehydrated more quickly and should be assessed promptly. Do not wait for diarrhoea or fever to settle before getting help for bloody vomit.

Could the blood be from retching or from another digestive source? How should I replace fluids safely? Do I need tests for dehydration, infection, or bleeding? When can I restart food, and which medicines should I avoid?