Green stool — when your feces look green — is usually the result of something you ate, such as spinach. Certain medications or iron supplements can also cause green stool.
Newborns pass a dark green stool called meconium, and breast-fed infants often produce yellow-green stools. In older children and adults, green stool is uncommon. It's rarely cause for concern.
Infants might have green stool as a result of:
- Not finishing nursing entirely on one side, thus missing some of the high-fat-content breast milk, which affects the digestion of the milk
- Protein hydrolysate formula (for babies with milk or soy allergy)
- Lack of normal intestinal bacteria in breast-fed infants
Children and adults
Causes of green stool include:
- Diet high in green vegetables such as spinach
- Food dyes
- Indomethacin – a nonsteroidal anti-inflammatory drug
- Iron supplements
- Medroxyprogesterone (Depo-Provera), a contraceptive drug
When to see a doctor
Call your doctor if you or your child has green stool for more than a few days. Green stool often occurs with diarrhea, so drink plenty of fluids and seek immediate medical attention if you or your child becomes dehydrated.