Opioid Induced Constipation (OIC)

What Is Opioid-Induced Constipation (OIC)?

Opioid-induced constipation (OIC) is a type of constipation caused by the long-term use of opioid pain medications. It occurs when opioids interact with the nerve endings in the intestine and slow down the entire digestive process. This can lead to a variety of uncomfortable symptoms such as: stomach pain, bloating, feeling of fullness, and difficulty passing stool.

What Causes Opioid-Induced Constipation?

Opioids work by binding to receptors on certain nerve cells in the brain and body. When opioids attach to these receptors, the signals sent from the body and brain can be inhibited or blocked, which can lead to several changes in the body’s normal functioning. The same type of inhibition occurs in the digestive system, where opioids can slow down the rate of digestion, leading to constipation.

Symptoms of Opioid-Induced Constipation

Symptoms of OIC may include:

  • Abdominal pain
  • Difficulty passing stool
  • Sense of incomplete evacuation
  • Hard, dry, or lumpy stool
  • Feeling of fullness or bloating
  • Less than three bowel movements per week

Treating Opioid-Induced Constipation

Treatment for OIC includes lifestyle modifications, including diet changes, physical activity, and drinking more fluids. Medication is also available to help manage the symptoms of OIC. These medications work by stimulating the muscles in the intestines, promoting peristalsis or the wave-like muscle contractions that help move food through the digestive tract. Other medications may work by changing the amount of fluid or electrolytes in the intestines. Additionally, biological therapies such as monoclonal antibodies may be used to help treat OIC.


Opioid-induced constipation is a common side effect of opioid use that can be treated with lifestyle changes and medications. It is important to talk with your doctor about any questions or concerns you may have with OIC or its treatment.