Paralytic ileus occurs when the muscle contractions that move food through your intestines are temporarily paralyzed. It’s a functional problem of the muscles and nerves that mimics an intestinal obstruction even when nothing is obstructing them. Food becomes trapped in the intestines, leading to constipation, bloating and gas.
Paralytic ileus occurs in the intestines, the long, tube-like passageway where food is broken down and absorbed before the waste is pushed out as poop. The intestines process your food along this journey through a series of wave-like movements called peristalsis. Paralytic ileus is the paralysis of these movements. It means that the muscles or nerve signals that trigger peristalsis have stopped working, and the food in your intestines isn’t moving. Accumulating stagnant food, gas and fluids in your intestines may cause you symptoms of bloating and abdominal distension, constipation and nausea. This is an acute condition, which means it’s temporary and reversible, as long as the underlying cause has been addressed.
Different kinds of conditions can inhibit your motility — your ability to process food through the digestive system. Paralytic ileus is a functional problem rather than a mechanical one. There's nothing physically blocking the passage of food in your intestines. The intestines just aren’t doing their job. Sometimes the entire digestive tract is affected, and sometimes ileus is localized in a particular bowel loop near the site of an injury or inflammation. Ileus is usually a temporary reaction of your body to trauma, such as surgery or infection. However, chemical factors, including medications, metabolic disturbances and electrolyte imbalances can also be at fault.
Symptoms may include:
If any of these symptoms are severe, you should treat them as an emergency.
Different kinds of conditions can cause temporary ileus, including:
Surgery is the most common cause of paralytic ileus. Surgeons expect and plan for it following abdominal operations. But other surgeries can also trigger it.
Inflammationof the abdominal cavity interrupts intestinal function. Inflammation may be caused by local irritation or toxic infection, such as:
Medications known to slow motility include:
Electrolyte imbalances that may be involved include:
Other conditions associated with paralytic ileus include:
Your medical history and a physical examination are often enough to diagnose ileus. An X-ray or abdominal ultrasound can confirm the condition by showing swollen and dilated segments of bowel without any mechanical blockage to explain them. Your healthcare provider may also use imaging tests to look for the cause if it isn’t already known. They may take a blood test to check your electrolyte and mineral levels.
If the cause is unknown, that will be addressed first. You may have an infection or disease that needs to be treated. If ileus occurs as a natural side effect of surgery, your healthcare team will already have a treatment plan in place. Treatment includes:
Normally, paralytic ileus passes within a few days. If it lasts more than five days, your healthcare provider may investigate further to see if there’s something else going on. Most cases improve without medication. If you’ve been treated for dehydration and other deficiencies, you should gradually resume normal eating. In rare cases, ileus can take longer to resolve.
A note from Cleveland Clinic
Paralytic ileus most commonly occurs as an expected side effect of surgery. This kind of ileus follows a predictable course, and your healthcare providers will be well-prepared to treat it during your recovery. Many of the other causes of paralytic ileus will have you already under medical care for those conditions. That means it will likely be spotted and treated early so you can avoid the complications of prolonged, untreated ileus. If you experience symptoms of ileus independently of another known condition, don’t hesitate to seek care. While it will usually pass on its own, it can be uncomfortable, dehydrating and depleting in the meantime. Healthcare can support you with hydration and nutrition therapies and relief for your symptoms.
Last reviewed by a Cleveland Clinic medical professional on 10/08/2021.
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