Bilious vomiting syndrome, the symptoms of which include appetite loss and severe, irregular bile vomiting, possibly indicates stomach and intestinal reflux, which occurs if a dog has not eaten for a considerable period, explains petMD. Other potential causes are diseases that cause intestine inflammation, which is called gastritis.
Dogs suffering bilious vomiting syndrome usually vomit substances containing bile in the morning or in the evening, and they experience nausea, stomach discomfort and weight loss, reports petMD. Older dogs, especially those that eat only once a day, are particularly vulnerable to the illness. The long period of stomach emptiness or inactivity between meals worsens bile reflux.
Bilious vomiting syndrome results from the unusual penetration of bile from the intestine into the stomach, leading to vomiting and irritation, according to petMD. To identify if bile is present, a dog owner should check for a watery substance with a yellow-green color in a dog's vomit. Bile that stays in the stomach and does not get expelled through vomiting may cause gastric reflux.
To diagnose bilious vomiting syndrome in dogs, veterinarians conduct a comprehensive physical exam that includes a urinalysis, full blood count and complete blood profile, notes petMD. Depending on the severity of the illness, treatment involves dietary changes that require small, frequent meals containing canned or liquefied foods. Veterinarians may also prescribe medications that improve gastric motility and reduce acid secretion.