IS OIC GETTING IN THE WAY?
Opioids bind to the mu-opioid receptors in the gut, which may lead to OIC1
About 40%-50% of patients receiving opioid therapy for chronic non-cancer pain report developing OIC2-5
In a longitudinal study of 493 adults with chronic non-cancer pain and OIC, 83% reported straining to pass bowel movements6
Laxatives do not address the underlying mechanism of OIC7
OIC is defined as a change in baseline bowel habits upon initiation of opioid therapy, including any of the following8:
- Decreased frequency
- Incomplete evacuation
- Harder stool consistency
Not all constipation is the same
Watch the video below to learn how opioids interact with the body, which can cause a distinct form of constipation called OIC.
Opioids are used to treat a wide variety of pain conditions including chronic and cancer related pain. These therapies have proven analgesic efficacy that are associated with a number of adverse eventssuch as nausea, vomiting, and constipation. Opioid receptors are highly expressed within the spinal cords. Dorsal Horn, which relays pain signals to the central nervous system and areas of the brain involved in pain transmission. Most opioids produce analgesia by binding to mu opioid receptors within the central nervous system, including the dorsal horn at the spinal cord. This reduces neuronalexcitability by impacting neurotransmission leading to an overall inhibitory effect on the neuron resulting in pain relief. However, opioid receptors are also widely distributed throughout the peripheral nervous system, including the gastrointestinal system. Constipation in opiate users is a common adverse event resulting from the activation of Mu opioid receptors on neurons in the myenteric and submucosal plexuses at the enteric nervous system or ENS within the GI tract.
This activation slows Gi motility and reduces secretions into the gut lumen. This can lead to a distinctform of constipation called opioid induced constipation. OIC. This consists in a change from baselinebowel habits characterized by any of the following, reduce bowel movement frequency, the development or worsening of straining to pass bowel movements, a sense of incomplete rectal evacuation or harder stool consistency. Various pharmacological approaches are used to treat opioidinduced constipation, including over the counter laxatives and prescription medications such as secretagogues and peripherally acting mu opioid receptor antagonist or PAMORAs. However, PAMORAs, are specifically targeted therapy that acts on the opioid receptor, reversing the constipating effects of opioid therapy.