Pyloric stenosis is an uncommon condition affecting the opening (pylorus) between the stomach and small intestine in infants. The pylorus is a muscular valve that holds food in the stomach until it is ready for the next stage in the digestive process.
In pyloric stenosis, the pylorus muscles thicken, blocking food from entering the baby's small intestine. Pyloric stenosis can lead to forceful vomiting, dehydration and weight loss. Babies with this condition may seem to always be hungry.
Pyloric stenosis can be fixed with surgery.