Bruce Springsteen announced Thursday that he’s postponing a slate of concerts in September on the advice of doctors who treating him for peptic ulcer disease.

Fans who aren’t familiar with this common and potentially serious gastrointestinal problem may wonder how it could sideline The Boss, who turns 74 later this month. Here’s what to know about the disease:

WHAT IS PEPTIC ULCER DISEASE?

It’s a condition marked by open sores that develop on the inside lining of the stomach and the small intestine, according to the Mayo Clinic.

The most common symptoms are burning stomach pain, heartburn, nausea and bloating or belching.

About 8 million people worldwide suffer from it.

WHAT CAUSES IT?

The most common cause of peptic ulcers is long-term use of anti-inflammatory pain relievers like aspirin or ibuprofen, according to Dr. Lawrence Kosinski of the American Gastroenterological Association.

“As you get older, they’re more injurious to the lining of the stomach,” he said.

Another cause may be an infection with bacteria called Helicobacter pylori.

Contrary to common belief, stress and spicy foods don’t cause these ulcers, though they can make the symptoms worse. Alcohol use, even at moderate levels, can also exacerbate the problem, Kosinski said.

IS IT SERIOUS?

Peptic ulcer disease can be dangerous, leading to bleeding and emergency situations such as perforation of the ulcer through the stomach.

Typical treatment uses common drugs called proton pump inhibitors, such as Prilosec, which can help heal the ulcers within four to six weeks.

People who are treated “recover completely from peptic ulcer disease,” Kosinski said.