vomiting

Vomiting, or emesis, is the forceful expulsion of stomach contents through the mouth. It is a protective reflex coordinated by the brainstem emetic center in response to signaling from the gastrointestinal tract, vestibular system, chemoreceptor trigger zone, and higher brain centers. It typically follows nausea and retching.

Common causes include acute gastroenteritis, food poisoning, pregnancy (hyperemesis), motion sickness, medications (chemotherapy, opioids, antibiotics), alcohol, migraines, metabolic disorders (diabetic ketoacidosis), and infections. Less common causes include central nervous system disorders, obstruction, and toxins.

Symptoms accompanying vomiting may include abdominal cramps, sweating, salivation, dizziness, and a feeling of needing to vomit. After vomiting, dehydration and electrolyte disturbances can occur, especially in children, the elderly, or those with ongoing illness.

Evaluation depends on age, severity, and accompanying signs. Red flags include vomiting with blood, projectile vomiting, severe dehydration, fever, stiff neck, confusion, severe abdominal pain, or persistent vomiting beyond 24–48 hours. Diagnosis may involve history, physical examination, pregnancy test, blood tests, stool tests, imaging, or endoscopy as indicated.

Treatment focuses on underlying cause and fluid/electrolyte replacement. Antiemetic medications (e.g., ondansetron, metoclopramide, promethazine) are commonly used. In pregnancy, treatment should be guided by clinicians to avoid teratogenic risks. Oral rehydration and small, frequent meals help once vomiting subsides. Severe dehydration or intractable vomiting may require hospitalization and intravenous fluids.

Prevention includes avoiding known triggers, maintaining hydration, and proper food handling.