What it feels like: A child has a dull ache that comes and goes, and often occurs in the middle of the night when his stomach is empty. He may also vomit and have bloody stools.
What's going on: Ulcers are relatively rare in American kids, and contrary to popular belief, they're not caused by emotional stress (although it can exacerbate them). Most are caused by the bacteria H. pylori, probably transmitted through food and water. Overuse of nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can also lead to ulcers, but this is only likely in kids who take pain relievers for a chronic illness like arthritis or for a sports-related injury.
What to do: Doctors can often identify H. pylori with a simple breath or stool test, though sometimes they need to do an endoscopy (a tube inserted through the mouth) to confirm that a child has an ulcer. If he does, your doctor will likely prescribe acid-blocking medication and antibiotics. To guard against NSAID-related ulcers, be judicious in handing out pain relievers to young athletes, and alternate NSAIDs with acetaminophen to control fever that lasts more than a few days.