Hi, the common causes for vomiting are
gastroenteritis (infection), gastritis, peptic ulcer disease, systemic infections,
appendicitis, intracranial hypertension, hepatitis, eating disorders, inner ear disorders, and certain medications. But since his blood tests, endoscopy and ultrasound reports are normal certain other causes need to be considered. Lung infections like pneumonia and bronchitis can irritate the diaphragm and cause vomiting.