HI. Associated diarrhea or constipation needs more attention than the vomiting as the root cause can be in the intestines giving vomiting as a reflex mechanism. I hope she has been well investigated for the intestines too. I would suggest to undergo such patients Contrast Ct abdomen, endoscopies ( camera endoscopy if available) , Enteroclysis if needed. It would be better f you consult a Gastro-Surgeon.