Yellow vomit is a common sign that the body is expelling bile, a digestive fluid normally found lower in the gastrointestinal tract. This yellow or greenish liquid indicates the stomach is likely empty of food and the vomiting reflex has been strenuous enough to draw contents from the upper small intestine. While a single episode can be benign, frequent or severe occurrences require understanding the underlying cause and recognizing associated warning signs.
What Bile Is and Why It Looks Yellow
Bile is a yellowish-green fluid that the liver produces continuously to aid in the digestion and absorption of fats. It is composed primarily of water, bile salts, cholesterol, and the pigment bilirubin. Bile is stored and concentrated in the gallbladder before being released into the duodenum, the first section of the small intestine, after a meal. The distinct color comes from bilirubin, a breakdown product of old red blood cells.
In the duodenum, bile helps to emulsify large fat globules, breaking them into smaller particles for enzymes to digest. When the stomach is empty, prolonged or forceful vomiting can cause the muscular valve (pyloric sphincter) separating the stomach from the small intestine to relax. This relaxation allows the bile to reflux back into the stomach, where it is then expelled.
Conditions That Cause Yellow Vomit
The most frequent reason a person vomits yellow is simply having an empty stomach, often following repeated episodes of vomiting from an acute illness like gastroenteritis or food poisoning. Once stomach contents have been evacuated, the body continues the retching reflex, drawing up bile-containing fluids from the small intestine. This can occur in scenarios like severe morning sickness or cyclic vomiting syndrome.
A structural issue known as bile reflux can also be the underlying cause, which occurs when the pyloric valve fails to close correctly. This malfunction allows bile to consistently flow backward from the small intestine into the stomach, causing irritation and inflammation of the stomach lining. Individuals who have had certain stomach surgeries, such as gastric bypass or gallbladder removal, are at a higher risk of developing this chronic condition.
A more serious cause of bilious vomiting is an intestinal obstruction, or bowel blockage, where a physical barrier prevents the normal passage of material through the intestines. The blockage forces digestive contents, including bile, to reverse direction and move back toward the stomach, leading to persistent vomiting. Conditions like adhesions from prior surgery, hernias, or tumors can create this blockage, necessitating urgent medical intervention.
Immediate Actions and Self-Care
After an episode of yellow vomiting, the most immediate and important step is to give the digestive system a period of complete rest. Experts recommend not consuming any food or fluid for at least two to three hours to allow the stomach lining to settle. Once the nausea has subsided, rehydration should begin gradually using small, measured sips of clear liquids.
Start with very small amounts, such as one tablespoon of water or an electrolyte solution every 15 to 20 minutes, which minimizes the risk of triggering another vomiting episode. Clear liquids, including weak tea, clear broth, or flat ginger ale, are preferred because they are easily absorbed and less likely to irritate the stomach. Avoid milk, coffee, and acidic juices during this initial phase of recovery.
If clear liquids are tolerated for several hours, you can slowly progress to bland, easily digestible foods. This includes items like plain rice, toast, applesauce, and bananas, which are low in fat and fiber and place minimal demand on the digestive process. Continue to eat small, frequent portions rather than large meals, and monitor the body’s reaction for at least 24 to 48 hours before attempting to return to a normal diet.
Symptoms That Require Emergency Care
While most instances of yellow vomit are self-limiting, certain associated symptoms indicate a potentially severe condition that requires immediate emergency medical attention. Severe dehydration is a primary concern, identified by signs such as profound lethargy, extreme confusion, or an inability to urinate for eight hours or more. A rapid heart rate, lightheadedness, or very dry, sunken eyes are also indicators of severe fluid loss.
Any significant change in the color or consistency of the vomit beyond yellow or greenish-yellow must prompt an immediate medical visit. This includes vomit that contains dark red blood, which may look like coffee grounds, or vomit that appears dark green or brown, suggesting a complete intestinal obstruction. Other red flags necessitate professional evaluation:
- Persistent yellow vomiting combined with severe, unrelenting abdominal pain.
- A high fever above 101°F (38.3°C) accompanying the vomiting.
- Vomiting that follows a recent head injury.
- The inability to keep down even small sips of fluid for more than 12 hours.