Headache after food poisoning: what to know

Food poisoning can remove water and salts through repeated loose stools or vomiting. That loss may cause thirst, dry mouth, darker urine, light-headedness, tiredness, and head pain. A raised temperature can also contribute. Some people eat and drink less while feeling nauseated, which adds to the deficit. Headache may continue briefly while the gut settles, even after the stomach symptoms begin to improve. The headache itself does not show which germ caused the illness.

Headache with ongoing abdominal pain, diarrhoea, fever, nausea, or vomiting can occur as part of the same illness. New confusion, marked weakness, or inability to keep fluids down suggests a more serious problem than routine recovery.

Rest in a cool, quiet place and take frequent small sips of water or an oral rehydration drink. Small amounts may be easier to keep down than a full glass. When appetite returns, choose simple foods and resume normal meals gradually. Avoid alcohol until you are recovered. Oral Rehydration Therapy may help replace fluid and salts; a clinician can decide whether IV Fluid Therapy is needed if drinking is not working. Follow the label of any pain medicine and check with a pharmacist if you are breastfeeding, pregnant, dehydrated, or taking other medicines.

Seek urgent medical help for a sudden or unusually severe headache, fainting, confusion, a stiff neck, trouble speaking, new weakness, repeated vomiting, blood in vomit or stool, or severe abdominal pain. Arrange medical assessment if you cannot keep fluids down, pass very little urine, remain dizzy when standing, or the headache is worsening instead of easing. Fever that persists or a diarrhoeal illness that is not settling also deserves review.

Ask whether your fluid and salt loss needs treatment, which pain reliever is suitable for you, and whether your continuing fever or bowel symptoms require testing. Mention when the headache began, how often you have vomited or passed stools, what you have been able to drink, and any medicines already taken.