Serious illness is less prevalent in primary care than in secondary care, therefore context is important. Vomiting accompanied by the symptoms listed in the box below may indicate a serious cause.
Red flag symptoms
- Severe abdominal pain – consider GI obstruction, acute pancreatitis or cholecystitis. If guarding, peritonism and absent or scanty bowel sounds are found, think acute abdomen.
- Rectal bleeding – consider GI inflammation or malignancy.
- Haematemesis – peptic ulcer, Mallory-Weiss tear, oesophageal varices, malignancy.
- Acute or focal neurological symptoms – CNS infection, tumour, stroke. Beware the patient with vomiting and unexplained headache.
- Chest pain or other features of acute coronary syndrome. Ischaemic gastroparesis should be considered in older patients with known atherosclerotic disease.
- Anorexia or weight loss may indicate cancer. Also consider psychiatric causes.
- Shock, volume depletion or life-threatening illness – consider adrenal insufficiency, which is a medical emergency, with nausea, vomiting, volume depletion and low sodium.
There are numerous possible causes of emesis. Careful history-taking, a focused examination, and appropriatesafety-netting should enable the GP to identify a serious cause.1,2
Common causes in primary care include gastroenteritis (usually viral), adverse drug reactions, motion sickness, pregnancy and vestibular disorders.
Less common causes are listed below.
Less common causes
- Cardiac: acute coronary syndrome, postural orthostatic tachycardia syndrome (POTS)
- Cyclical vomiting syndrome
- Endocrine: diabetic gastroparesis, diabetic ketoacidosis, hypoglycaemia, hypercalcaemia, hypothyroidism, hyperthyroidism, adrenal insufficiency
- ENT: Menière’s disease, acoustic neuroma
- GI/hepatobiliary: biliary colic, cholecystitis, pancreatitis, hepatitis, mucosal irritation of upper GI tract (such as gastritis, peptic ulcer), food poisoning, bowel obstruction, gastric neuromuscular disorders
- Malignancy: nauseogenic tumours include ovarian, renal, stomach, pancreatic and small cell lung cancers. Liver metastases can cause anorexia associated with nausea
- Neurological: migraine, CNS infections, tumours, stroke, vestibular nerve lesions, Parkinson’s disease, traumatic brain injury
- Psychiatric: bulimia and anorexia nervosa, drug overdose, severe anxiety
- Renal: nephrolithiasis, renal failure, pyelonephritis
- Other: alcohol, cannabis, post-operative chemotherapy and radiotherapy
History and examination
Firstly, establish that your patient has vomiting, as opposed to regurgitation, retching or nausea.
Secondly, narrow down the diagnosis; in particular, try to distinguish between a GI and non-GI cause.
Thirdly, decide whether referral or further investigations are required, and how urgently.
Some key features of the history and examination include:
- Timing of vomiting - is it acute or chronic, intermittent or constant? The vomiting component of viral gastroenteritis usually lasts 12-48 hours. Cyclical vomiting syndrome is characterised by symptom-free weeks followed by days of extremely severe nausea and vomiting. It usually begins in childhood.
- Nature of vomit and relation to meals - partially digested food and delay in vomiting after eating may indicate gastric outlet obstruction or gastroparesis. Bilious vomiting suggests small bowel obstruction and faeculent vomiting suggests colo-intestinal fistulae.
- Associated symptoms - ask about fever, diarrhoea, pain, bleeding, weight loss and anorexia. Conduct a brief systemic enquiry.
- Past medical and surgical history - previous abdominal surgery is a risk factor for acute bowel obstruction. Check also for a history of cardiac, thyroid or adrenal disease, diabetes, malignancy, immunosuppression and mental health problems.
- Travel - consider tropical diseases in returning travellers with fever and vomiting.
- Pregnancy - ask all women of childbearing age about their last menstrual period and consider pregnancy as a possible cause.
- Drugs - NSAIDs, antibiotics, antidepressants, opioids, anti-arrhythmics, theophylline, digoxin, metformin, exenatide, oestrogen and progesterone can all induce nausea or vomiting, as can most drugs if taken in large enough quantities. Ask, as appropriate, about alcohol, cannabis, recent chemotherapy and radiotherapy.
Examine for both causes and complications of vomiting. Check temperature and blood pressure, do a full abdominal examination, assess hydration and nutritional status. Examine other systems (such as cardiac, endocrine, neurological, ENT) as indicated by the history.
These will be guided by the history and examination findings. Primary care tests might include:
- pregnancy test
- blood glucose
- full blood count and electrolytes
- stool cultures
When to refer
Most cases of viral gastroenteritis will settle within a few days with simple measures, such as oral fluids, rest and analgesia.
Consider urgent admission in the following situations:
- people with severe or intractable vomiting who may need IV fluids or other supportive treatment
- people with complications of vomiting, such as dehydration, electrolyte imbalance, aspiration or Mallory-Weiss tear
- those with emergency underlying causes, such as acute abdomen or meningitis
- frail or immunosuppressed patients.
For suspected cancer, NICE guidance recommends the following:3
- for people aged 60 and over who have nausea or vomiting with weight loss, consider an urgent (within two weeks) direct access CT scan (or ultrasound if CT is not available) to look for pancreatic cancer.
- for people aged 55 and over who have nausea or vomiting with raised platelet count, weight loss, reflux, dyspepsia or upper abdominal pain, consider a non-urgent direct access upper GI endoscopy to look for oesophageal or stomach cancer.
- Dr Suchita Shah is a portfolio GP and population and global health specialist in Oxford
BMJ Best Practice. Assessment of nausea and vomiting, adults. 7 November 2019.
- Furyk JS, Meek R, McKenzie S. Drug treatment of adults with nausea and vomiting in primary care. BMJ 2014, 349, g4714.
- NICE. Guidance on Suspected cancer: recognition and referral. NG12. 2015. Updated January 2021.