Endoscopies are safe procedures that rarely cause complications for the patient, although in rare cases a patient may have an allergic reaction to anesthesia. However, in rare cases an endoscope may puncture the digestive tract, causing a hole (perforation) to form. If this occurs, it may require surgical repair. Pain, bleeding and infection also sometimes occur as the result of an endoscopy.

However, it is more likely that patients who experience complications will have only minor irritation or bleeding of the digestive tract.

Rare complications associated with upper endoscopies include:

• Severe irregular heartbeat
• Pulmonary aspiration (in which foreign matter enters the trachea [windpipe])
• Fever
• Breathing problems

Rare complications associated with endoscopies of the lower gastrointestinal tract include:

• Dehydration as a result of using too many laxatives or enemas
  
  
• Cardiac arrhythmias (abnormal heart rhythms)
  
  
• Bursting of combustible gases in the colon when polyps are removed
  
  
• Breathing problems

In addition, patients should contact their physician if they experience any of the following symptoms:

• Unexplained or chronic abdominal or chest pain, including heartburn
• Swallowing difficulties or pain when swallowing
• Nausea and vomiting or reflux
• Indigestion
• Weight loss (unexplained)
• Unexplained and persistent changes in bowel habits
• Abdominal pain
• Diarrhea
• Black or tarry stools or bleeding from the rectum