Yellow-colored foods and drinks can sometimes cause yellow vomit, and some people with respiratory or nasal infections may also throw up yellow mucus that has accidentally been swallowed. Most of the time when vomit is yellow, however, it is due to the presence of bile, a digestive juice used to break down fats. Bile in vomit is more likely to occur when a person expels the entire contents of his stomach. A person may also vomit bile if this digestive juice backs up into the stomach, or if he suffers from a bowel obstruction.
On of the most common, and least dangerous, causes of yellow vomit is the presence of yellow food or liquid in a person's stomach. For example, a person may have yellowish vomit if he gets sick after eating a yellow food, such as corn. Yellow-colored drinks, particularly yellow cocktails, can also cause a person to expel this type of colored vomit.
A respiratory or sinus infection can also cause yellow vomit in some cases. During these types of infections, large amounts of mucus are usually produced. This mucus will often contain infectious agents, like bacteria, and it can also leak down the back of the throat and into the stomach. Large amounts of yellow mucus in the stomach can cause a person to have yellowish vomit.
Bile, or gall, is another common cause of yellow vomit. This digestive juice is typically very bright yellow in color. It is produced in the liver and stored in the gallbladder until it is needed.
Small quantities of bile are almost always present in vomit. Due to the presence of food articles as well, however, usually makes bile less noticeable. Prolonged bouts of vomiting will often expel the entire contents of a person's stomach. When this happens, bile can be forced into the stomach, resulting in higher quantities of bile in vomit, making it appear bright yellow.
Yellowish vomit in bile can also be caused by a more serious condition. Bile reflux is a condition in which large amounts of bile back up into the stomach. This can cause vomiting as well as pain and heartburn.
A small bowel obstruction can also cause a person to vomit bile. When there is an obstruction in a person's small bowel, it will prevent food from passing through. This can cause the bowel to expel its contents, including large amounts of bile. Other symptoms of an intestinal obstruction may include constipation, abdominal pain, and a swollen abdomen.
It is very important for a person to check with a medical professional if he has yellow vomit. This is especially true if symptoms like abdominal pain and fever are present. Although this color of vomit may be harmless, it is important to rule out any serious medical conditions.