Symptom · Abdomen
Nausea
Also known as: feeling sick, queasiness
The unpleasant sensation of being about to vomit. It is coordinated by centres in the medulla that respond to signals from the gut, the inner ear, the blood (toxins, drugs, hormones) and the higher brain (smells, fear, pain).
What it is
The unpleasant sensation of being about to vomit. It is coordinated by centres in the medulla that respond to signals from the gut, the inner ear, the blood (toxins, drugs, hormones) and the higher brain (smells, fear, pain).
Common causes
Gastroenteritis and food poisoningWith vomiting, diarrhoea and cramps.
MedicationsAntibiotics, painkillers (opioids, NSAIDs), chemotherapy, iron, metformin.
Early pregnancyMorning sickness in the first trimester.
MigraineNausea accompanies most attacks.
Motion sickness and inner ear disordersWith vertigo.
Reflux, gastritis and overeatingUpper abdominal discomfort with nausea after meals.
Alcohol and hangover
Less common causes
Bowel obstruction or appendicitisNausea with pain and a swollen abdomen.
Heart attackNausea and sweating may be the only symptoms, especially in women and diabetics.
Raised pressure in the skullMorning nausea and headache.
Kidney failure, liver failure, diabetic ketoacidosisMetabolic causes with drowsiness.
Gallstones and pancreatitisWith upper abdominal pain.
Often occurs with
Seek urgent care if
- Nausea with chest pain, sweating or breathlessness
- Nausea with severe abdominal pain or a swollen, rigid abdomen
- Nausea with a severe headache, stiff neck or confusion
- Persistent nausea in pregnancy with inability to keep fluids down
Conditions to read about
MigraineGastro-oesophageal reflux diseasePeptic ulcerAppendicitisGallstonesHeart attack (myocardial infarction)Pancreatitis
How it is investigated
Educational content. This page explains what a symptom can mean so that the anatomy and the medical reasoning make sense. It cannot tell you what is causing yours: only a clinician who can examine you and order tests can do that.