Understanding Sudden Illness: Common Causes of Nausea & Vomiting

Random nausea/vomiting has a broad differential. Common causes:

Gastrointestinal

• Gastroenteritis (viral, bacterial, foodborne)
• GERD / acid reflux
• Gastritis, peptic ulcer
• Food poisoning / intolerance
• Gastroparesis

Systemic / Metabolic

• Hypoglycemia
• Hyperthyroidism
• Adrenal insufficiency
• Uremia (renal failure)
• Diabetic ketoacidosis

Neurological / Vestibular

• Migraine (vestibular migraine)
• Motion sickness
• Increased intracranial pressure
• Concussion

Other

• Pregnancy (early)
• Medication side effects (chemo, antibiotics, opioids, NSAIDs)
• Psychogenic (anxiety, stress)
• Cyclic vomiting syndrome

Red Flags – Seek Urgent Care

• Hematemesis, melena.
• Severe abdominal pain.
• High fever, dehydration signs.
• Neurologic deficits.
• Persistent >24–48 hours.

Pattern recognition + targeted workup guides diagnosis.