My Baby Is Vomiting Green or Yellow (Bile)
The short answer
Bilious (green or bright yellow) vomiting in a baby is a medical emergency until proven otherwise. While older children and adults occasionally vomit bile with prolonged vomiting, in infants, green vomiting can be a sign of a bowel obstruction such as malrotation with volvulus, which requires emergency surgery. If your baby vomits green or bright yellow fluid, seek immediate medical attention.
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By Age
What to expect by age
0-1 month
Bilious vomiting in a newborn is a surgical emergency until proven otherwise. The most concerning cause is malrotation with midgut volvulus, where the intestine twists on itself, cutting off blood supply. This can lead to intestinal death within hours if not treated surgically. Other causes include duodenal atresia, jejunal atresia, or other congenital bowel obstructions. If your newborn vomits green or bright yellow fluid, go to the emergency room immediately. Do not wait to see if it happens again.
1-6 months
Bilious vomiting remains a red flag at any age in infancy. While some conditions like malrotation can present later in infancy, intussusception (where one segment of bowel telescopes into another) also becomes a possibility, typically after 3 months. Bilious vomiting combined with abdominal distension, bloody stools (currant jelly appearance), lethargy, or inconsolable crying requires emergency evaluation with imaging studies such as an upper GI contrast study or ultrasound.
6-12 months
At this age, occasional green-tinged spit-up after eating green vegetables (like peas or spinach) is not the same as bilious vomiting and is harmless. True bilious vomiting is bright green or fluorescent yellow and occurs without recent green food intake. Intussusception peaks at 5-9 months and classically presents with intermittent severe abdominal pain (episodes of drawing up legs and crying), vomiting that may become bilious, and eventually bloody stools. This requires emergency treatment.
1-3 years
In toddlers, bilious vomiting is still concerning but has a broader differential. Prolonged vomiting from gastroenteritis can eventually produce bile-colored vomit after the stomach has been emptied. This is less alarming in the context of an obvious stomach bug where the child was initially vomiting food, then clear fluid, then bile. However, bilious vomiting as a first or early symptom, or bilious vomiting with severe abdominal pain and distension, still requires urgent evaluation to rule out obstruction.
What Should You Do?
When to take action
- Green-tinged spit-up after eating green-colored foods like pureed peas, spinach, or green beans in an older infant
- Yellow-tinted vomit after prolonged vomiting from a clear stomach virus, where the child initially vomited food and then clear fluid first (context of known gastroenteritis in a child over 1 year)
- Your toddler has an episode of bile-colored vomiting during a stomach virus but is otherwise keeping down some fluids and not in significant pain
- You are unsure whether your baby's vomit is truly green/bilious or just a food-related color
- Any episode of bright green or bright yellow (bilious) vomiting in a baby under 12 months, especially without preceding food-related explanation - go to the emergency room immediately, as this could indicate a life-threatening bowel obstruction
- Bilious vomiting at any age combined with severe abdominal pain, abdominal distension, bloody stools, lethargy, or your child appearing very ill - this is a surgical emergency requiring immediate evaluation
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
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