Other metabolic d/o: liver and kidney dz, hypercalcemia, hypothyroidism, DKA
Pregnancy - in particular first trimester
Odors - primary or linked to prior unpleasant events (e.g. chemotherapy)
Acute, severe pain for any reason
Systemic malignancies
Generalized systemic infections or acute illness
Meds - many - dx made on basis of temporal relationship, recognizing possible contribution
Myocardial ischemia
Cyclic vomiting syndrome: Unusual process that causes episodic vomiting, which can be severe and lead to hypovolemia. Can be frequent (e.g. every 5 min) for hours to days. Also abdominal pain. More common in kids than adults. Diagnosis made by excluding other causes and pattern of repetition. Precipitants not clear.