My pet vomits food that looks partially digested once in every three to five months. When she vomits she keeps vomiting bile even after her stomach gets empty, and it takes about 5-6 hours for it to subside. She looks a little down on those days. Her appetite and energy comes back after 2-3 days, but we don't know what might be causing it. Ever since we had her neutered we've been seeing hematuria from an unknown cause (idiopathic cystitis?), and we've been treating it with stress-relieving food suggested by our vet. We take her to the vet regularly, but should we do something about the vomiting?