An obstruction can be partial, which may get better without surgery. A complete blockage is more likely to need intestinal surgery.
Mechanical obstructions
Mechanical obstructions are when something physically blocks your intestine. In the small intestine, this can be due to:
adhesions, which are made of fibrous tissue that can develop after any abdominal or pelvic surgery or after severe inflammation
volvulus, or twisting of the intestines
intussusception, a “telescoping,” or pushing, of one segment of intestine into the next section
malformations of the intestine, often in newborns, but can also occur in children and teens
tumors within your small intestine
gallstones, although they rarely cause obstructions
swallowed objects, especially in children
hernias, which involve a portion of your intestine pushing outside the muscle or tissue in your body or into another part of your body
inflammatory bowel disease, such as Crohn’s disease
Although less common, mechanical obstructions can also block your colon, or large intestine. This can be due to:
stool stuck in your colon or rectum (impacted stool)
adhesions from pelvic infections or surgeries
ovarian cancer
colon cancer
meconium plug in newborns (meconium is the stool babies first pass)
volvulus and intussusception
diverticulitis, the inflammation or infection of bulging pouches of intestine
stricture, a narrowing in the colon caused by scarring or inflammation
Nonmechanical obstruction
Your small and large intestines normally work in a coordinated system of movement. If something interrupts these coordinated contractions, it can cause a functional intestinal obstruction.
This is generally known as a nonmechanical obstruction. If it’s a temporary condition, it’s referred to as an ileus. It’s called a pseudo-obstruction if it becomes chronic, or long-term.
Causes for an ileus include:
abdominal or pelvic surgery
infections, such as gastroenteritis or appendicitis
some medications, including opioid pain medications
electrolyte imbalances
Intestinal pseudo-obstruction can be caused by:
Parkinson’s disease, multiple sclerosis, and other nerve and muscle disorders
Hirschsprung’s disease, a disorder in which there’s a lack of nerves in sections of the large intestine
disorders that cause nerve injury, such as diabetes mellitus
hypothyroidism, or an underactive thyroid gland