The precise cause of diminished blood flow to the colon isn't always clear. But several factors can increase your risk of colon ischemia:

  • Buildup of fatty deposits on the walls of an artery (atherosclerosis)
  • Dangerously low blood pressure (hypotension) associated with heart failure, major surgery, trauma or shock
  • A blood clot in an artery supplying the colon or, less commonly, in a vein (venous thrombosis)
  • Bowel obstruction caused by a hernia, scar tissue or a tumor
  • Surgery involving the heart or blood vessels, or the digestive or gynecological systems
  • Other medical disorders that affect your blood, such as inflammation of the blood vessels (vasculitis), lupus or sickle cell anemia
  • Cocaine or methamphetamine use
  • Colon cancer (rare)

The role of medications

Certain medicines also can lead to ischemic colitis, though this is rare. They include:

  • Nonsteroidal anti-inflammatory drugs
  • Some heart and migraine medications that shrink blood vessels
  • Hormone medications, such as estrogen
  • Antibiotics
  • Pseudoephedrine
  • Certain medications for irritable bowel syndrome
  • Chemotherapy medications
Oct. 10, 2012