Signs and Symptoms of Pyloric Stenosis

The most significant symptom of pyloric stenosis is vomiting. Infants who have this condition usually vomit within 30 minutes of a feeding. At first, vomiting may be mild and sporadic, but it eventually worsens so that forceful projectile vomiting occurs after every feeding. In some cases, the vomit contains blood, since constant vomiting can irritate the stomach lining and cause bleeding.

Additional symptoms of pyloric stenosis include the following:

  • Abdominal pain
  • Belching
  • Constipation or diarrhea (stools may be loose, green, and contain mucus; bowel movements may stop altogether)
  • Dehydration (loss of body fluids and electrolytes through frequent vomiting; signs include lethargy, fewer wet diapers, crying without tears, saggy skin, dry mouth and tongue, cracked lips, sunken eyes, and a depressed fontanel [soft spot in a newborn's skull])
  • Hunger (infants with pyloric stenosis cannot keep down or digest food)
  • Jaundice (excess blood levels of bilirubin, causing yellowing of the skin and the whites of the eyes)
  • Lump in the abdomen (The thickened pylorus often can be seen and felt.)
  • Stomach contractions after feeding but before vomiting begins (called peristalsis; visible wave of contractions as the stomach muscles try to move the food through the pylorus to the small intestine)
  • Weight loss (or weight gain that slows or stops)

Pyloric Stenosis Complications

Although pyloric stenosis can be corrected in most cases, the condition is serious. Infants who are not diagnosed quickly are at increased risk for developing further stomach irritation, dehydration, and electrolyte loss. They may experience shock (extremely low blood pressure), malnutrition, and stunted growth. Death from pyloric stenosis is rare, but can occur if symptoms continue for too long.

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 27 Aug 2008

Last Modified: 01 Oct 2015