Why is my dog throwing up yellow fluid? If your dog's vomit is yellow and foamy, you're likely dealing with bile and may be wondering what causes him to bring up this bright, yellow fluid in the the first place. The explanations for bile vomiting in dogs may be various, but understanding what bile is and when it's more likely to be vomited up, can help you.
A dog vomiting bile in the morning can be easily helped by just following some simple dietary guidelines, but in some cases, bile vomiting can be a sign of something serious that needs prompt veterinary attention.
What's Exactly Bile?
Sure, the easy explanation is that bile is simply a yellow fluid that dogs vomit every now and then, but there's more into it if you want to know exactly what you are dealing with. To be precise, bile is a bitter, digestive fluid that is alkaline rather than acid and is secreted by the dog's liver. It is then transferred into the dog's gallbladder, where it is stored until food is digested. Bile is then released into the small intestine (duodenum) just below the stomach through the bile duct where it aids in the digestion of fats.
How Does Bile End up In Dog Vomit?
Normally, bile stays nicely put in the intestine as the pyloric valve, a closure between the stomach and intestine, keeps contents from the small intestine from backing up. However, in some abnormal cases or when the vomiting center of the brain commands to initiate the vomiting reflex, the pyloric valve may open up allowing bile to flow backwards into the stomach. If the dog vomits, then through strong stomach contractions, the bile is forcefully brought up from the stomach to the esophagus and out the mouth. If the dog fails to vomit though, the bile may sit in the stomach with the risk of causing gastric reflux.
When a dog vomits bile, it's often a sign that the dog's stomach is empty. Since the stomach is empty, you will not see food but only see this liquid yellow fluid. The bile, therefore, becomes more evident since it's only fluid, versus being mixed with food where it's barely noticeable. If your dog vomits shortly after eating, you will see mostly food at first, but then, if he continues to vomit, once the stomach is emptied from all of its food contents, you'll start seeing only bile.
Vomiting Bile in the Night or Early Morning
As mentioned, bile is most evident when a dog vomits on an empty stomach. A dog that vomits in the night or early morning, is mostly vomiting on an empty stomach as most dogs are fed during the day and then go through the night with no food until the morning or later in the day. The dog's stomach generally empties within 2 hours after eating, so a dog who vomits past this time is likely to vomit for the most part bile or something difficult to digest.
A Vicious Cycle
There are two ways dogs may end up vomiting bile: the bile may back up from the intestines into the empty stomach with the end result of irritating the dog's stomach, or the dog's stomach may produce excess gastric acid which irritates the stomach lining causing the dog to vomit stomach acid along with the bile. Unless the dog is fed several meals during the day which helps soak up these acids, the stomach remains empty again and the dog may again feel nauseated and may vomit again creating a viscous cycle of dog vomiting because the bile irritates the empty stomach and the stomach being empty because of vomiting.
Breaking the Vicious Cycle
Often dogs who vomit in the night/early morning are only fed once a day. The way to prevent the vomiting/empty stomach cyle is to feed the dog several small meals during the day, such as breakfast, a midday snack, then dinner and a snack before going to bed or in the middle of the night/very early morning. Food helps protect the stomach from the effects of gastric fluids. However, sometimes dogs predisposed to producing excess gastric fluids may need medications to keep the situation under control as these dogs will keep vomiting bile no matter how many times they're fed. Commonly prescribed medications include antacids such as Tagamet, Pepcid and Zantac. This condition is commonly referred to as "bilious vomiting syndrome."
Small Dogs Vomit Bile More
Small dogs are particularly predisposed to vomiting bile because their stomachs are tiny and they have a fast metabolism, explains veterinarian Dr. Fiona. So when these tiny dogs are fed a meal, they use their food at a much faster rate than a larger dog and soon before they know it, their stomachs are empty.
Other Bile Vomiting Causes in Dogs
[adinserter block="5"]While it's true that vomiting bile in the morning can often be suggestive of bilious vomiting syndrome, it's also true that vomiting bile can be indicative of many other conditions.
This is why seeing your vet for dog upset stomach is always your best bet.
Possible conditions of repeated bile vomiting may include a gastric motility abnormality, bile reflux gastritis, giardiasis and inflammatory bowel disease.
The Importance of Proper Diagnosis
A proper diagnosis in this case can really make a difference when it comes to vomiting bile. For instance, when a dog is vomiting after eating, a common remedy is to fast the dog for about 12 hours and then feed a bland diet; whereas, in dogs vomiting bile in the morning the treatment can be totally opposite, these dogs actually need food to get better!
Bile vomiting per se' though isn't really indicative of any particular condition as it ultimately just means that the dog has vomited on an empty stomach. A dog who has ingested something toxic may vomit food and keep vomiting until the stomach empties and pure bile appears. Same may happen with dogs who have blockages, dogs who have pancreatitis, dogs who vomit from eating grass, dogs with upset stomach from changing foods, dogs who are vomiting from stress or suffer from several other digestive and systemic disorders. So the bottom line is to have your dog see the vet if he's vomiting bile on a frequent basis, and even more so if there are other accompanying symptoms such as lethargy, loss of appetite, abdominal pain and weakness.
Did you know?
The typical color of dog feces comes from the release of bile. Indeed, dogs affected by conditions that interfere with the proper secretion of bile develop grey or light colored feces.