Differential diagnosis:

• Posetting - In infants, simple small volume vomits of milky fluid (posseting) is extremely common after feeds.
• GORD
• Infection -
  • More forceful vomits in infancy can be a non-specific sign of infection. Examples include gastroenteritis, pneumonia, acute otitis media, tonsillitis, meningitis or urinary tract infection.
  • For this reason, a thorough examination including an ENT examination is usually recommended for very young children presenting with vomiting
• Whooping cough - Vomiting after prolonged periods of coughing in an unvaccinated child is suggestive of whooping cough (Bordetella pertussis infection).
• Pyloric stenosis
• GI obstruction
• Malrotation (neonates)
• Appendicitis
• Testicular torsion
• Brain tumour - Vomiting, especially if coupled with other neurological signs/symptoms, might indicate a space-occupying lesion caused by a tumour

Causes of vomitting in older children

In older children and teenagers, additional causes of acute vomiting may include:

• diabetic ketoacidosis
• More chronic causes of vomiting in older children include cyclical vomiting and migraine.
• Early morning headaches and vomiting suggests raised intracranial pressure.
• In teenagers, it is important to take a wider approach and consider alcohol, drug use (especially cannabis), bulimia and pregnancy.